了解区块链不做小白
近几年，随着比特币火热的炒作，区块链技术也被越来越多的人所关注。本文将介绍区块链、智能合约和矿工三个关键词，为您介绍区块链技术的基本概念。
区块链是一种分布式数据库，它记录了每一笔交易的历史记录，并将其保存在由多个节点组成的网络中。每一笔交易都会被记录在一个“区块”中，这些区块会按照一定的规则连接在一起，形成一个安全可靠的“链”。区块链的优点在于，它不受任何中心化机构的控制，每一笔交易都会被分布式的节点所记录，因此不可篡改，透明可靠。
智能合约是一种由区块链技术支持的自动执行协议，它可以用来实现自动执行、自动结算和自动执行合同的功能。智能合约是基于区块链技术的，它可以将交易和执行自动化，使得交易更加安全可靠。智能合约的优点在于，它可以让交易变得更加快捷、安全和可靠，不受任何中心化机构的控制，而且消除了信任问题。
矿工是区块链技术中最重要的一环，他们负责维护整个区块链网络的安全性和稳定性。矿工是一种特殊的节点，他们负责对新的交易进行验证，然后将其记录到区块中，并将其广播到整个网络中。矿工的作用是保证整个区块链网络的安全性和可靠性，是区块链技术发展的基石。
本文介绍了区块链、智能合约和矿工三个关键词，介绍了区块链技术的基本概念。区块链是一种分布式数据库，智能合约是一种由区块链技术支持的自动执行协议，而矿工则是负责维护整个区块链网络的安全性和稳定性的重要环节。未来，区块链技术将会给我们带来更多惊喜，让我们拭目以待！
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1. Zihang talks about currency: Newbies in the currency circle don’t even know what “blockchain” is
First of all, I believe that before everyone understands blockchain , you must have heard of Bitcoin first, right? Because we all know that the first people to hold Bitcoin made money!
But one point of view is wrong: What point of view? Many people believe that Bitcoin is the blockchain. In fact, Bitcoin is just a type of blockchain asset, and it is the earliest blockchain asset. The concept of blockchain comes from Bitcoin. The reason why Bitcoin can be so arrogant and exist independently without relying on any organizational structure is because the bottom layer is supported by blockchain technology.
Just like our mobile phones can run, the bottom layer is supported by Android or ios system. So what kind of technology is blockchain? Why is it so powerful? Can make Bitcoin so valuable! The English name of blockchain is block chain, and block means block. You can imagine that if you fall or bump into something, you may have bruises, right? The blocks in the blockchain contain some The data block of transaction information, something, may have a bruise, right? The block in the blockchain contains some data blocks of transaction information, and the chain in the blockchain connects the data blocks. , this is like a big ledger. Anyone who uses this blockchain ledger can directly query any transaction information arranged in order, and it is difficult to tamper with. So how does it do it?
Let’s give a simple example using local materials: There are now a total of 100 readers who are linked through the Internet to form a blockchain network system. Please pay attention! We are not reading this article now, but a blockchain network system. In this system, I ask one of the people, say this person is called panda, to borrow 10 yuan, and then panda transfers the 10 yuan to me in the network system. Then my account or wallet increased by 10 yuan. As for panda, who lent money to Bibi, his account lost 10 yuan. After this transaction is completed, other people in our blockchain network system, after seeing it, will take a small notebook and record the matter. My account will increase by 10 yuan, and panda's account will decrease by 10 yuan.
That’s not right, then what are you doing when you are full and have nothing to do? Why should we record these small and medium-sized "bad things"? It’s because the network system will pay wages to those who participate in recording. As long as she records it once, the system will automatically reward tokens that are common in this network system. As long as there is money, everyone is willing to do anything. In reality, there are actually countless individuals in a blockchain system, which means that our group not only has only 13 people, but they don’t know each other yet, but they can all communicate with each other on the system chain.Transmit each other and record the transactions in the blockchain network in order. Suppose that one day I want to default on the debt and do not plan to pay back 10 yuan to panda. Then I must convince 51% of everyone in the blockchain network system. or more, ask them to delete or tamper with the record.
If it were replaced by real-world computing power, it would be almost impossible and would require huge costs. This is the characteristic of blockchain technology - decentralized collaboration, transaction data is difficult to tamper with, and transaction information is transparent and queryable. Its main function is to solve two problems that are difficult to solve on the Internet - one is trust and the other is value transfer.
The so-called trust, according to the above scenario, is that I may default on the loan and take the money and run away; the value transfer is: my borrowing account should increase by 10 yuan, while the panda account becomes -10 Yuan money exchange. Then we may have questions again, isn't Alipay and WeChat payment solved now? Wouldn’t it be enough to just confirm the account and transfer the money directly and send a red envelope? Yes, Alibaba and Tencent exist based on solving these two problems. but! Thinking about it from another perspective, if a mere blockchain technology can solve these two problems now, can huge and complex institutions like Alibaba and Tencent be abandoned?
Rebuilding a new network system to apply it to more fields is on the way.
Because, the final conclusion is: this technology builds the value of Bitcoin, then this technical logic can also be used in many other fields. Maybe one day you will be happy to discover - Huh? I am now using a product from a certain blockchain technology company! ? Just like many years ago, one day you unknowingly used QQ and started to learn to watch videos and play games online. Having said that, what does it mean that Bitcoin is an early asset of the blockchain? Why does it add value? According to the scenario mentioned above, the so-called tokens are the tokens issued by the system to everyone in the group by participating in accounting. These tokens are blockchain assets. (The behavior of everyone participating in bookkeeping is commonly known as mining.) Bitcoin itself is the value token of the Bitcoin blockchain network system
Then why is it Will it add value? Because its quantity is limited, the number of issuances is determined at one time from the beginning of the establishment of the network system and will never be issued additionally.
So, in the future, the more people participate in accounting in a certain blockchain network, the number of people who get it will gradually decrease, and value-added will become inevitable. This is like Alibaba's early stocks. After the Alipay application is launched, the more people participate in using it, the more it is needed, and Alibaba's stocks will inevitably increase in value.
Of course, there are currently many projects applying blockchain technology, but most of them have not found a landing scenario. However, the more people believe that a project created using blockchain technology will be used in the future. Need, then thisThe price of the project’s tokens will be pushed up. Therefore, there are far more investment opportunities in blockchain assets than in the ordinary stock market. If you invest in a value project, then it may skyrocket like Bitcoin a few years ago, which skyrocketed from 130,000 per coin to a little over 40,000 now. In other words, you don’t need to consider any investment opportunities in other varieties. A few years ago, if you bought Bitcoin with your eyes closed and then ignored it and just went about your own business, the return on this investment would be 100 times in one year.
Profit! How much is that right? The opportunities in this industry are far more than these. Almost all currencies will have the opportunity to rise or fall sharply, but this range of rise and fall is not like the 10% daily limit in stocks. Blockchain assets disappear from trading around the world 24 hours a day, and It is T+0, and there is no limit on the increase or decrease. The price of any variety is completely affected by the limit on the increase or decrease and the pursuit of funds. Most varieties have experienced an increase of more than 100% throughout the year. High This kind of investment opportunity is also difficult to find in other markets.
The currency circle is like Tai Chi. Only when a person is in a state of tranquility can he feel the opponent's strength and intention in the push hand for the first time. What I felt at the time was that only by clearing myself could I receive information to the maximum extent and quickly, and make correct judgments and responses. The same is true in the currency circle.
This material is for learning reference only and does not constitute buying or selling advice. Buy and sell based on it at your own risk!
2. How to introduce the blockchain in 3 minutes in a simple and easy-to-understand manner and what its commercial value will be in the future
There is a real story about an engineer from Ant Financial. I wrote a blind date resume, and the job description in it was "code farmer", but no one clicked it for a long time. Later, he changed his work experience to "blockchain" and received 381 love letters at once.
From workers in high-tech industries to square dancing aunties, it seems that everyone is participating in the blockchain carnival. So what exactly is the seemingly mysterious blockchain? After reading the following content, you will have completed the journey from beginner to beginner.
1. What is blockchain?
To put it bluntly, the blockchain is "everyone keeps accounts together." Any database needs a big housekeeper to be responsible for "accounting" (maintaining the system and entering data). But after using blockchain technology, the concept of this "central steward" disappears, and each of us can participate in accounting. So the question is, whose record will ultimately prevail? Of course it is the person who completes the work well and quickly. A system that strictly adheres to fairness will fundamentallyThis person is selected based on the algorithm, the contents recorded by him are written to the ledger, and the contents of the ledger during this period are sent to all other people in the system for backup.
Any new thing must have unique advantages if it wants to develop rapidly, and the same is true for blockchain technology. First of all, blockchain technology ensures the security of the system. In the absence of a central steward, everyone is a defender of the home, which means that destroying some nodes has no impact on the system at all. Second, the recording process cannot be cheated. Everyone in the blockchain system has the same ledger, and the entire process is open and transparent. The system will determine the final result based on the opinions of the majority. It is difficult for an individual to hack into so many computers at the same time, and it is meaningless to just modify one's own results. Who would do such a thankless task? Third, and most importantly, the blockchain completely abandons the existence of "credit intermediaries". Credit intermediaries are the platforms we must pass through when transferring money, such as traditional banks. Now any two strangers can directly complete mutual trust transfers, and the efficiency has been improved not only a little!
3. What is the use of blockchain technology? ?
As mentioned above, the main advantages of blockchain are that it does not require intermediary participation, the process is efficient and transparent, the cost is very low, and the data is highly secure. That is to say, any industry that has needs in these three aspects can use blockchain technology. Here are a few examples:
In the banking industry, the use of blockchain technology is equivalent to updating a digital, secure and tamper-proof General ledger books. In fact, Swiss bank UBS and Barclays Bank in the UK have already begun experiments, hoping to use it as a way to accelerate back-end system functions and clearing and settlement capabilities. Some institutions in the banking industry claim that blockchain may reduce middleman costs by 20 billion.
In terms of car rental, blockchain also has great potential. A future customer selects the car they want to lease, entering it into the blockchain's public ledger; then, sitting in the driver's seat, the customer signs the lease agreement and insurance policy, while the blockchain updates the information simultaneously. This is a foreseeable future for car sales and car registrations.
In terms of medical and health care, blockchain technology allows hospitals, patients and all parties in the medical benefit chain to share data in the blockchain network.data without having to worry about data security and integrity. This means more accurate diagnosis, more effective treatment, and an improvement in the health system’s overall ability to deliver cost-effective care.
Blockchain is not cold-blooded. It has been implemented in applications that are closely related to our lives. For example, the application of Ant blockchain ranges from public welfare, to mutual insurance, to traceability of product authenticity, to traceability of rental housing.
In 2018, blockchain will "return to the world."
Blockchain, do you really understand it? Since it says three minutes, let’s give a simple answer.
1. What is blockchain;
2. What are the benefits of blockchain;
3. What are the uses of blockchain;
4. Blockchain technology and existing problems;
Let’s first look at the first question: What is blockchain
Let’s look at it literally. Blockchain is called Blockchain in English. This is a very good word. The English name is well chosen and the Chinese translation is also very beautiful.
1. What is a "block"?
You can think of it as a record, or anything, which forms such a record during the production stage. This thing can be any physical or virtual object in the Internet of Everything.
For example, if you generate a Bitcoin, which is a thing, it actually corresponds to a block. This block is a record of what it is.
When you produce a bottle of medicine in the future, a block is actually generated when this bottle of medicine is produced. When it leaves the factory, it needs to be recorded once, and this corresponds to it one-to-one.
This is the first dimension.
To make it easier to understand, for example, each of us is born with a unique identifier, which is our DNA. All species in the world have different DNA. Every individual's DNA is different.
Your parents can name you Zhang San, Li Si, Wang Wu. These names can be repeated, just like a bottle of medicine, whether it is aspirin or penicillin, these can also be repeated. famous. However, human DNA is different. Even if you have identical brothers and sisters, your DNA is different, so this is your unique identifier. And once your DNA is formed, it cannot be changed. This is a benefit of the blockchain.
2. What is a "chain"? The chain is actually a process. You can think of it as a transaction process. After this bottle of medicine leaves the factory, it enters the warehouse from the workshop and passes through a certain door, and it will record the process.
Of course this requires the computer to automaticallyThe cost of manual recording is too high. Then, packing is a process, and transportation to the cargo transfer station is another process. Then it is loaded into a car and transported to the wholesale station, which is the next process.
Every step of the process is recorded. It is a process to go from the wholesale station to the store, it is another process for the people in the store to receive this batch of medicines and put them on the shelves, and it is still a process for you to buy them. Finally, when the whole process is connected, you will have a way to track the entire process of this bottle of medicine and know its authenticity, because once this bottle of medicine is produced, it will be bound to the blockchain, as well as to people and people. The same is true for DNA binding, which cannot be changed, but it can be seen and tested.
The doctor can also determine whether this person is you by testing DNA. So in terms of nature, if we virtualize it, it is actually a smart contract. You have signed a sales relationship with one of your customers. Once this happens, it cannot be changed. Then everyone can only execute it. This execution process is the same as the tracking of drugs I just talked about.
Second question: What are the benefits of blockchain?
1. Mathematically speaking, it is very beautiful. It changes from the past that you had to own something before you could know its properties to that you don’t own it, but you can ask questions Learned many details about it.
Mathematically speaking, this is a perfect asymmetric situation. You can tell whether it's true or false, but you can't change it.
2. Theoretically speaking, blockchain is very safe. For example, if you participate in the process of a bottle of medicine, others cannot see this information. That is to say When you buy this bottle of medicine, you can know where it comes from, but others cannot.
For the same reason, for example, if we sign a contract, others can verify the contract. If you go to a bank for a loan, he can ask you the amount.
However, he cannot obtain this contract, and he cannot steal this contract from your computer.
Blockchain also has some very interesting properties. For example, a block chain can be divided into two at will, or several can be combined into one, etc.
3. Blockchain is transparent, which means that everyone abides by this algorithm and there is no special agreement in private. So, if you believe in this algorithm, it means you believe in me and believe that I didn't do anything fishy. I will not secretly do anything in the contract to make you suffer losses.
This is a beautiful place theoretically and mathematically.
In the third block, let’s take a look at the uses of blockchain
1. Bitcoin is a cryptocurrency, and the Ethereum currency that everyone uses now is also a cryptocurrency. Of course, you can make another one based on it, either Zhang three coins or Li four coins. As for whether it can replace the currency of the future, this is aDoubtful.
2. Financing, we used to divide financing into three stages: the first stage is to get a loan from the bank. If you want to open a restaurant, you need to mortgage something. The second stage is that you issue some stocks and I sell 10% of the stocks, so that I can obtain part of the funds.
The third stage is actually crowdfunding. For example, if I want to write a book, it may cost 50,000 yuan for the publishing house to publish it. If any of you can give me 50 yuan at the beginning, I will use it in the future. Once the book is written, give everyone a copy. You will get the book, and of course I will publish it. But there is a problem. For example, I sell this book for 100 yuan and you get it for 50 yuan. What if my book sells very well, assuming I sell 100,000 copies, but you don’t seem to benefit from me? what to do?
Is there a fairer way to measure everyone's contribution? One way is to issue a cryptocurrency (ICO). When the business we do becomes bigger in the future, you can benefit from it.
3. Smart contract, for example, sign a contract. In the future, the smart contract can become like this. All the nodes in the middle are determined when the contract is signed, such as building or decorating a house for you. , your payment must be given to me at any stage of the decoration. If you accept it, no problem, the payment will be automatically given to me.
You can even sign with my supplier, which means that as soon as my money arrives in my account, I will give it to my supplier immediately. This will eliminate many triangular debt problems in the future, including the problem of arrears to migrant workers.
Blockchain can also be used for property registration, car registration, etc. Of course, another great use is gambling. In fact, gambling is the most willing to adopt new technologies because it is closely related to money.
After talking about the benefits of blockchain, let’s take a look at the technology and existing problems of blockchain.
Today’s blockchain is basically the second generation and the first generation. It is the Bitcoin generation. It has many problems. It is not a platform, but is actually a specific application.
The second generation is represented by Ethereum. It is a platform on which you can issue your own coins, and it removes the concept of mining machines, so its transaction costs will be much lower. . The reason why ICOs are everywhere today is because with Ethereum, you can issue coins. Unlike in the past with Bitcoin, you had to completely copy its formula and copy it again. Today you are on Ethereum. , it is easy to issue your own currency, just like you can easily make your App on the Android operating system today.
There are three problems with Bitcoin transactions
1. The transaction delay is very long. I asked people who specialize in Bitcoin transactions and the delivery time ranges from two hours to two hours. Days wait, so it is very inconvenient for you to use it to launder money. After the RMB is converted into US dollars, it may take two days.If it falls by 20%, you lose 20% of your money.
2. It cannot be distributed. Like Bitcoin, the early people took away a lot of its shares, so how to distribute it in the future is also a problem. No one knows clearly, so it is difficult to use it as a currency. a currency. Because if it really becomes a currency that everyone uses, it will be equivalent to the first few people taking away a large part of the world's property.
3. Transaction costs are high. For example, a cup of coffee at Starbucks in the United States costs $2.50 on average. You usually pay money at the counter, and the transaction time is only one minute. If you want to use Bitcoin, you have to wait two hours before you can get your coffee, and the transaction costs are extremely high, the electricity bill alone is $20. In other words, if you pay $2.50 for coffee, the transaction cost of electricity is $20, so this is unrealistic.
Blockchain has high risks. This risk is not only a technical risk, but also a policy risk. In fact, this is also an opportunity. Whoever solves this problem will get the opportunity. Its transaction costs are also very high, so whoever can develop new underlying technologies and reduce this transaction cost will make a lot of profits in the future.
Some people say it is the next generation of the Internet. I don’t agree with this, but it will definitely be a supplement to the Internet. Some people say whether it can subvert the central bank, but this is not certain, because there is no reason why the central bank or these big banks cannot do this themselves, so those who expect it to subvert the central bank may be too happy too early.
Perhaps in the end it was these large financial institutions in the past that used the blockchain to update themselves.
Talk in the vernacular and get useful information!
Literally, blockchain is blocks and chains, and some relationship between them. It is essentially a distributed accounting method and a network database system that cannot be tampered with.
The current development directions include digital currency, payment, smart contracts, defi finance, web3 and so on. It is still in the initial stage of development and is a back-end technology. Most projects are still speculating and financing.
Today’s Afghanistan may best prove the value of Bitcoin, and there is no problem with value storage
Blockchain is not just a technology, it is a way of trust transfer, value The way it is delivered may have huge potential in the future.
Keywords: block, chain, database, ledger, Afghanistan, currency speculation, value, technology, market
First, what is a blockchain? Blocks and chains are an accounting method and a form of network data storage.
Literally speaking, blockchain refers to blocks and chains. This block actually records the transaction records of the entire network, or the execution result data of smart contracts, etc.
Every once in a while, a block will appear on the entire network.This block records all transfer data, and blocks need to be connected by some kind of "chain".
This chain is an encryption algorithm. Some information of the previous block is used to calculate and obtain certain information of the next block. They are linked together. The latter block can trace back to the previous block and needs to be modified. The next block must modify the previous block, all the way to the first block. Regarding the details of these issues, I have written many articles before. If you are interested, you can go back and take a look.
Blockchain is actually an accounting method, or a database storage method. Please pay attention to what I say below. The whole process is the operating mechanism of blockchain.
Each node in the entire network has the same status and runs the same program. This program is used to collect, encapsulate and package all transaction record data records that occurred in the entire network within a period of time. Then broadcast it to the entire network
Let’s take Bitcoin as an example. Once this packaging and encapsulation is completed, you can obtain the right to produce the block. A certain amount of Bitcoin can be issued every time a block is produced. Since the nodes in the entire network run the same program, there is no center to control everyone. Therefore, the currency issued is irrevocable and cannot be changed.
How to decide who has the right to make a block? This requires the use of the so-called consensus mechanism, which is to establish a rule and use who produces the block as the benchmark to solve the problem of network consistency. The mainstream consensus mechanisms include POW mechanism and POS mechanism. Proof of work and proof of stake. Proof of work, who does more work, and proof of equity, who stakes more assets
Pow means that everyone calculates a difficult mathematical problem together, whoever calculates it Whoever comes out has the right to produce the block. Pos means that everyone takes out their family assets as mortgage, and whoever mortgages more. It is possible to be selected as a block producing node.
The essence of this approach is that you have to pay a certain price and receive a certificate of investment, which essentially builds a kind of trust.
When all these tasks are completed, a block can be produced, and the block will be connected to the previous block one by one. This is the entire block sequence. Note that the entire blockchain world will produce many blocks, connected to one chain after another, but everyone will only recognize the longest chain, and short chains will be discarded.
To put it simply, each network node uses a program to package transactions within a period of time, and then connects the transaction blocks one after another and saves them in each node, but an encryption algorithm will be used in the process. Ensure that node information is not leaked, ensure that user information is encrypted, and ensure that the information in the block is not hacked or tampered with.
Second, the block The current development of the chain, various projects and significance, at this stage are more about currency speculation, and there is no problem with value storage.
Blockchain has been developing for twelve or three years since the Bitcoin white paper in 2008. It has also experienced various evolutions and developments.
For example, now it has gone from being able to issue currency in a distributed way to now having huge functional expansion. The landmark event is the birth of the Ethereum smart contract.
I have explained many times that a smart contract is an automated contract signed by two or three parties. It will be automatically executed as long as the conditions are met. It is essentially a program with infinite possibilities and the judge in the blockchain world. Various functions can be input into the program, and the program exists. Blockchain has become rich and colorful.
Current blockchain applications mainly include the following aspects: smart contracts, payments, cross-chain assets, oracles, defi, web3 storage, etc. I will briefly mention two. Let’s take an example and talk about its commercial application.
For example, defi applications are quite popular on Ethereum now. Defi is decentralized finance. Abbreviation for decentralized finance.
What does it probably mean? It is to move all financial-related businesses in real life, such as mortgages, insurances, and loans, onto the blockchain.
This field is very popular now, and the reason is simple. It is very suitable for blockchain. As I said, a smart contract on the blockchain is a contract. If the contract conditions are met, execution can be automatically triggered.
In the past, it might have been very troublesome for you to go to the bank to apply for a loan. You had to sign various signatures and verify them, and the bank might not be open on weekends and nights
But with blockchain The network operates 24 hours a day. If you want to run various assets on it and do various mortgage transactions, you only need to click and there is a software terminal.
Of course, the real assets will be frozen in the process and mapped to virtual assets. After the transaction is completed, they will be exchanged for real assets. Cross-chain technology and oracle technology may also be used in this process, which I have written in detail in other articles.
It roughly means cutting off banks through decentralization, and direct point-to-point transactions. The security of transactions is guaranteed by blockchain technology, code and cryptography.
There is also the current web3 storage class. For example, the leading project fil. His vision is to take out all the scattered hard drives. Break all the data and information that need to be stored on the network into small pieces
and then distribute them to the entire network. When we want to use network data in the future, we no longer need large network database or server. In this way, Internet giants cannot charge high service fees. There is no way to maintain a monopoly.
If you want to obtain stored information, just take a taxi online like dd. You pay for a taxi, so that information on the Internet can flow freely. Costs will drop significantly.
Of course, these visions are grand and huge, and the current blockchain development is still in its early stages. There are still some technical difficulties to be overcome and some underlying systems to be established, but there is no problem in this direction.
The original digital asset projects like Bitcoin have now been proven to be very safe. Just like this situation in Afghanistan, the first thing that comes to my mind is Bitcoin. He is the first violent and unplunderable asset.
Your house may be occupied and blown up, and your gold may be robbed. And if you have Bitcoin, it's much easier. He can't snatch this thing away, because the mnemonic phrase and private key are in your mind, and he doesn't even know whether you have this thing in your mind. If you want to pass it on to your child, just ask him to memorize the key and mnemonic phrase.
It is precisely because we are now in a stage of financing and bubbles that all the news you see on the Internet is still speculation.
Also, this thing is a back-end technology. For example, Guangdong Province already has blockchain invoices. For example, there are already some blockchain apps for judicial certification, but for the front-end For you, you can't feel it. There is an extra string of hash codes on the invoice, can you tell the difference?
This is why when it comes to blockchain now, everyone is speculating on coins, but in fact it has certain applications and future technical logic.
Third, it is essentially a mechanism of trust, a method of value transmission, and an exploration of social governance methods.
What is the essential value of blockchain? The most important thing is that it is a way of credit transfer. Because there is enough credit, real-life assets and property values can be spread on the Internet in the form of information codes.
Mainly in these aspects.
First, before Bitcoin, people did not know how to protect a piece of information, because information on the Internet can actually be copied. Bitcoin solves the problem of uniqueness of information assets. With scarcity, there is value in transactions and storage.
The second is decentralization and disintermediation. We used to do everything. All require some kind of intermediary. For example, when you borrow money, a bank acts as an intermediary, and when you buy a house, various institutions and real estate agencies act as intermediaries.
You cannot buy or sell directly. Because you don't have enough credit. We usually come to find a third party, but the third party is usually made up of people and may also do evil.
For example, the master who could whip five lightning whips a while ago. If he calls you all kinds of names at the beginning, you may be frightened. You won't know he is a liar until he is punched and lying straight there. This is human credit, unreliable
Blockchain ensures trust through code, cryptography, and consensus mechanisms.use. We no longer need a powerful third party. Note that this third party will often become a monopoly boss.
The third is to reduce the cost of coordination, communication and entry barriers.
If we want to become richer, we need to trade in the market. Transactions require coordination and division of labor. Essentially, the companies and organizations we work for are intermediaries.
You have to integrate your resources through this kind of intermediary, transform your labor force, your brainpower, and your ingenuity into final products and sell them on the market.
The smart contract technology of blockchain technology can break up these contracts in a decentralized manner. People in the market can combine freely to establish a new type of organization that is completely transparent and cannot tamper with the rules, which is a blockchain autonomous organization. The future of this kind of organization may be more promising than that of ordinary joint-stock companies.
You can join or quit an organization at will, and the trust between you and others has been resolved. You can cooperate with others and sign smart contracts to complete joint collaboration and complete a certain product. We no longer have to worry about some big capitalist taking advantage of everyone and getting the bulk of the profits.
So the Bitcoin blockchain is essentially a big social experiment, through the consensus mechanism, the decentralized decision-making method, and the distributed signing of smart contracts. Gradually and completely change the original appearance of our society. Restore the original ideal of market economy, peer-to-peer, direct transactions between people.
To summarize. Blockchain is a block of information connected together through an encryption algorithm. It is essentially an accounting method and a network data structure
Through decentralization, you can do finance, storage, and decentralize many things, but now it is still very In the initial stage, most projects are still in the stage of speculation, financing and concept development.
The value storage capability of the blockchain has been proven to be problem-free, very safe, and cannot be plundered by violence.
The essence of blockchain solves the problem of credit intermediary, and at the same time can reduce the cost for people to work together, lower the threshold for enterprise entry, improve social efficiency, make social transactions larger, and allow We are richer.
I recommend the book linked below, it is easy to understand. Like You Pump tells the history of the birth of blockchain, the underlying technical logic of blockchain, and some mainstream projects. Learn some knowledge about blockchain, feel more at ease, and no longer worry about whether it is a scam.
3. What is blockchain? A cartoon to help you understand (a must-read for beginners)
The word "blockchain" actually In the early cryptography circles, the underlying technology of Bitcoin was called "Bitcoin", and in English it was referred to as Bitcoin starting with a capital B.Bitcoin is a network system or network protocol.
However, due to public confusion, people are now very resistant when talking about Bitcoin, thinking that Bitcoin is synonymous with illegality, scams, pyramid schemes, and another phenomenal bubble in Internet finance! As a result, people had to merge all the underlying technologies (timestamps, proof-of-work mechanisms, etc.). In order to distinguish them from Bitcoin, they renamed them Blockchain, which translated into "blockchain". This is how the term “blockchain” appeared.
Blockchain is not a single technology, but a collection of a series of technologies.
How should we understand blockchain? Let’s first use the love story that everyone loves to talk about as a simple example. Establish a simple blockchain model, then the following situation will occur when falling in love in this blockchain model:
In the future, all men and women of the right age will fall in love and the entire process of marriage commitment will be blocked by all other men and women of the right age. Consensus, all the stories that happen between two people will form a block.
All other men and women are the chain. If a third party intervenes or you violate your partner, others can see it, and you will never find a partner in the future.
To be precise, the blockchain is a "full center" system, that is, every node on the chain is the center.
Trial marriages for men and women to fall in love, post on friends, show affection, promise to love each other for a lifetime and be known by all other marriageable men and women are the applications of blockchain. If one day one party breaks their promise, don't think that deleting the photos will be useful, because every piece of it has been recorded by all marriageable men and women.
Cannot be deleted or changed, this is blockchain technology.
4. What is blockchain: This explanation of blockchain is more understandable
Blockchain is an important concept of Bitcoin. It is essentially a disintermediation The database, as the underlying technology of Bitcoin, is a series of data blocks generated using cryptographic methods. Each data block contains information about a Bitcoin network transaction and is used to verify the validity of its information (anti-counterfeiting). ) and generate the next block.
Blockchain is a new application model of computer technologies such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithm.
In a narrow sense, blockchain is a chain data structure that combines data blocks in a sequential manner in chronological order, and is cryptographically guaranteed to be non-tamperable and non-transformable. Fake distributed ledger.
Broadly speaking, blockchain technology uses block chain data structures to verify and store data, uses distributed node consensus algorithms to generate and update data, and uses cryptography to ensure data transmission and access. A new way to program and manipulate data securely using smart contracts composed of automated script code.Distributed infrastructure and computing methods.
(4) Understand the blockchain without being a novice. Extended reading:
The evolution method of the blockchain is:
▪ Blockchain 1.0 - digital currency;
▪ Blockchain 2.0 - digital assets and smart contracts;
▪ Blockchain 3.0 - distributed applications in various industries Landed.
Blockchain characteristics:
1. Disintermediation. Due to the use of distributed computing and storage, there is no centralized hardware or management organization in the system. The rights and obligations of any node are equal. The data blocks in the system are jointly maintained by nodes with maintenance functions in the entire system.
2. Openness. The system is open. In addition to the encryption of private information of all parties to the transaction, the blockchain data is open to everyone. Anyone can query the blockchain data and develop related applications through the public interface, so the entire system information is highly transparent. .
3. Autonomy. The blockchain adopts consensus-based norms and protocols (such as a set of open and transparent algorithms) to enable all nodes in the entire system to exchange data freely and securely in a trustless environment, changing trust in "people" to trust in "people". Machine trust, any human intervention has no effect.
4. Information cannot be tampered with. Once the information is verified and added to the blockchain, it will be stored permanently. Unless more than 51% of the nodes in the system can be controlled at the same time, modifications to the database on a single node are invalid, so the data in the blockchain is stable. Extremely high performance and reliability.
5.Anonymity. Since the exchange between nodes follows a fixed algorithm, the data interaction does not require trust (the program rules in the blockchain will judge whether the activity is valid by itself), so the counterparty does not need to disclose its identity to make the other party trust itself. Very helpful for credit accumulation.
5. Read a small example of what blockchain is, and don’t be a novice!
Here is a rough introduction to what blockchain is, but if you want to go deeper, If you want to understand blockchain, you should read more related articles.
Blockchain can be introduced in one sentence. It is a decentralized distributed ledger. Blockchain is not a certain thing. You can think of it as the Internet. No one will think that the Internet is an object. Blockchain is a new model. If you think of it as a ledger, all transaction information is in this book. The decentralization feature makes it completely independent of third parties.
Blockchain is essentially a decentralized database. Once the content in the database is recorded on the chain, it cannot be tampered with. All content can be traced back to its source. Centralized products may be affected by Therefore, blockchain traceability is also often used to trace the source of items.
There is still a lot of knowledge about blockchain. This is just a simple concept. It will take time to understand it in depth.Take some time to read the news and learn about its practical applications. You can see more in Crypto Finance.
6. How to learn blockchain
Two steps, the first step is to determine the direction, and the second step is to determine the details. There are several directions:I'm just a novice who wants to know what it is.
I want to work in the blockchain industry, doing development, operations, products, and even blockchain entrepreneurship.
The details of each direction are purple:Direction 1
I want to understand what the blockchain is and what the various coins do.
Let’s start with Bitcoin. Here we recommend "Bitcoin" edited by Li Jun, Chang Chai, etc., which can help you understand the consensus wisdom behind Bitcoin, the principle of decentralization, the history of Bitcoin, etc. Next, let’s research various currencies. The larger domestic chains include QTUM and NEO, and the larger foreign chains include EOS, ETH, etc. Study their white paper, team, history, twitter, telegram groups and other places where you can get in touch.
At the same time, you also need a place where you can read market trends, exchange ideas, and read articles. Here are some commonly used apps recommended. For example, the commonly used APP blockfolio to check prices; to check information, block information, news, and even find a place to brag, you can use the Babbitt APP; for currency information, you can refer to the non-small app, which has a lot of content. Among them, Babbitt APP is the one I use most because its news is reliable and will not be faked.
Direction 2
Blockchain industry
As far as I know, most of the current practitioners in the blockchain industry have transferred from finance or computer majors. If you are a college student and want to work in the blockchain industry, you may consider majoring in finance or the computer industry. If you are already working and want to join the blockchain industry, then you need to learn the following content. "Blockchain: From Digital Currency to Credit Society" by Chang Chai and Han Feng will introduce you to the basic knowledge of blockchain. "Blockchain Technology Guide" can help you deepen your understanding of blockchain technology. "Blockchain Revolution" can take you into a revolution that is about to happen. Overall, there is a lot to learn.
7. What is blockchain technology? Popular explanation of what blockchain is
Blockchain has been at the forefront since the end of October.
What is blockchain technology
Although blockchain has been around for more than ten years, many people still don’t know much about this technology.
Blockchain is a new application model of computer technologies such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithms. From an application perspective, blockchain is a distributed ledger.
So, why is the blockchain called the blockchain?
Because the blockchain itself is a series of linked blocks, on these blocks,They are all filled with transaction records. Blocks are very similar to database records. Every time data is written, a block is created. With the expansion of information exchange, one block continues with another, and the result is called a blockchain.
What are the characteristics of blockchain technology?
Simply put, blockchain has the characteristics of decentralization, openness, non-tampering, and anonymity.
1. Decentralization:
In the blockchain system, there is no center.
In the blockchain model, it is distributed accounting and storage. Each node self-verifies, transmits, and manages information. Each node is the center, which is decentralization.
2. Openness:
The blockchain system has the characteristics of openness. The data is open and anyone can query the blockchain data and data through the public interface. Develop related applications.
3. Information cannot be tampered with:
In the blockchain system, once the data is written, the tampering cannot be undone unless 51% of all data nodes are controlled. Forge a record that does not exist. Therefore, blockchain technology has a certain degree of security.
4. Privacy and anonymity:
The cryptography technology in the blockchain can effectively achieve identity concealment.
The identity information of each node does not need to be disclosed or verified, and information transfer can be done anonymously. It can only be accessed with the authorization of the data owner, thus ensuring data security and personal privacy.
Xiao Li lent 10,000 yuan to Xiao Wang. Xiao Li found two people in common and Xiao Bai to prove it. This accounting model is a centralized accounting model, and Xiaobai is the center.
However, a year later, when Xiao Li wanted to get the money back, Xiao Wang Shikou denied that he had lent him the money. It turned out that Xiao Wang introduced Xiao Bai’s girlfriend to his company. a job.
This is the disadvantage of centralized accounting.
Xiao Li learned a lesson and gained wisdom. In the future, when someone asked him to borrow money, he said on WeChat in the village that I would lend so-and-so how much money. In this way, everyone in the village knew that Xiao Li How much money did Li lend to whom?
In this way, when Xiao Li asks for debt again in the future, the other party will not deny the issue, because a consensus mechanism has been established in the minds of the people in the village: How much did you borrow from Xiao Li? .
This is the advantage of decentralized accounting.
Because after all, there are many people to testify about this transaction. If it seems to be a fraud, it will be unless more than half of the people in the village are bought. However, the price is very high.
In fact, these characteristics of the blockchain are all to solve the problem of "trust". The rich application scenarios of the blockchain are also based on the blockchain's ability to solve the problem of information asymmetry. At the same time, Blockchain also helps achieve collaborative trust and consistent action among multiple entities.
What are the applications of blockchain?
In addition to digital currency, there are many application scenarios of blockchain.
1. Medical field
Blockchain helps realize smart medical care, such as going to the hospital to see a doctor. Through the blockchain model, the patient’s medical status, cases, treatment status, etc. are all Clearly visible, saving a lot of medical resources.
2. Copyright field
Blockchain can prove the authenticity and uniqueness of the copyright of works, from the birth to the transfer of audio, video, pictures, text and other works. Can be tracked and recorded, and form tamper-proof information.
3. Logistics field
After applying blockchain in the logistics field, goods can be traced from production to consumption.
4. Food safety
Is blockchain used for food safety? Through blockchain traceability, one can easily trace the past and present life of their food.
5. Securities trading
For example, traditional securities trading requires the coordination of multiple institutions to complete, while the blockchain system can independently complete one-stop transactions. This service can make securities trading simpler and faster.
However, many people have big misunderstandings about blockchain. The biggest misunderstanding is: blockchain = Bitcoin
In fact, blockchain and Bitcoin is not the same thing. Blockchain is the underlying technology of Bitcoin, and Bitcoin is the first application of blockchain.
8. Comic illustration: What is blockchain
Comic illustration: What is blockchain
What is blockchain?
Blockchain, English Blockchain, is essentially a decentralized distributed database. Anyone can become a node of this huge network as long as they set up their own server and connect to the blockchain network.
Since the blockchain is essentially a database, what exactly is stored in it? Let’s take a look at the basic unit of blockchain: Block.
A block is divided into two parts:
1. Block header
The block header stores the header information of the block, including the hash value (PreHash) of the previous block. The hash value of the block body (Hash), the timestamp (TimeStamp), etc.
2. Block body
The block body stores the detailed data (Data) of this block. This data contains several rows of records, which can be transaction information or some other information.
What does the hash value just mentioned mean?
Everyone must have heard of MD5. MD5 is a typical hash algorithm that can convert a string of plaintext of any length into a string of fixed length (128 bits). This string is the hash value.
In our blockchain, a more complex hash algorithm called SHA256 is used. After a series of complex calculations, the latest data information (such as transaction records) will eventually be converted into a 256-bit hash value string through this hash algorithm, which is the Hash in the block header. The format is as follows:
Blocks and Hash have a one-to-one correspondence, and Hash can be regarded as the unique identifier of the block.
How are different blocks related to each other? Rely on Hash and PreHash to associate. The PreHash value of each block is equal to the Hash value of the previous block.
Why do we need to calculate the hash value of the block?
Since the blockchain is a chain structure, there must be a head node (the first block) and a tail node (the last block) of the chain. Once someone calculates the hash value of the latest data in the blockchain, which is equivalent to packaging the latest transaction records, a new block will be created and connected to the end of the blockchain.
The Hash of the new block header is the hash value just calculated, and the PreHash is equal to the Hash of the previous block. The data in the block body stores the transaction records before packaging, and this part of the data information has become unmodifiable.
This process of calculating Hash values and creating new blocks is called mining.
The server used for massive calculations is called a mining machine.
The workers who operate calculations are called miners.
What is so difficult about calculating hash values? Let’s give the most superficial explanation. The formula for calculating the hash value is as follows:
Hash = SHA-256 (Hash of the last block + basic information of the new block + transaction record information + random number)
Among them, the transaction record information is also a series of hash values, and its calculation involves a data structure Merkle Tree. Interested friends can check the relevant information, we will not introduce it for now.
The key computational difficulty here lies in the generation of random numbers. In order to increase the difficulty of Hash calculation, the wretched inventor of the blockchain requires that the first 72 bits of the Hash result must be 0. This probability is too small.
Since (the Hash of the last block + the basic information of the new block + the transaction record information) is fixed, can we obtain a Hash that meets the requirements?Totally depends on the value of the random number. Miners must go through massive calculations and repeatedly generate random numbers in an attempt to "get lucky" before they can get the correct Hash and successfully mine.
At the same time, the block header also contains a dynamic difficulty coefficient. When the world's hardware computing power becomes faster and faster, the difficulty coefficient of the blockchain will also increase, making the entire network capable of completing the task every 10 minutes on average. A new block is generated.
Friends, do you understand how difficult mining is? It should be added that different blockchain applications are different in details. The mining rules described here take Bitcoin as an example.
Applications of Blockchain
The concept of Bitcoin (BitCoin) was first proposed by Satoshi Nakamoto in 2008, and then based on this idea, open source software and P2P built on it were designed and released. network. Bitcoin is a P2P form of digital currency. Peer-to-peer transmission means a decentralized payment system.
What is a P2P network?
Traditional currencies are uniformly issued by the central bank, and all personal savings are uniformly managed by banks. This is a typical centralized system.
Bitcoin is deployed on a decentralized network composed of many peer nodes around the world. Every node is qualified to record and issue this digital currency.
As for the underlying data storage of Bitcoin, it is based on blockchain technology. Each transaction in Bitcoin corresponds to a row in the block body data. A simple diagram is as follows:
Each row of the transaction record contains a timestamp, transaction details, and digital signature.
The table is only for ease of understanding. The actual stored transaction details are anonymous, and only the wallet addresses of the payer and payee are recorded.
As for digital signatures, they can be understood as anti-counterfeiting marks for each single transaction, generated by an asymmetric encryption algorithm.
Next let’s talk about the rewards of Bitcoin miners:
The Bitcoin protocol stipulates that miners who mine new blocks will receive rewards. Starting from 2008, it is 50 Bitcoins, and then halved every 4 years. , currently 12.5 Bitcoin in 2018. The new Bitcoins in circulation are all born in this way. No wonder everyone is so eager to mine Bitcoins!
Advantages and Disadvantages of Blockchain
Advantages of Blockchain:
1. Decentralization
Blockchain does not rely on a central node. The data of the entire system is All peer nodes in the entire network are jointly maintained and can store and verify data. In this way, unless the attacker hacks more than half of the nodes in the entire network, the entire system will not be destroyed.
2. Information cannot be tampered
The data in the block cannot be tampered with. Once the data is tampered with even a little bit, the hash value corresponding to the entire block will change accordingly, and it will no longer be a valid hash value, and the subsequent linked blocks will also be broken.
Disadvantages of blockchain:
1. Excessive consumption of energy
To generate a new block, a large amount of server resources must be used to perform a large number of unnecessary trial calculations, which seriously consumes electricity.
2. Network delay of information
Take Bitcoin as an example. Any transaction data needs to be synchronized to all other nodes. The synchronization process will inevitably be affected by network transmission delay, resulting in a long time consuming.
A few additional points:
1. Part of the content of this comic refers to Ruan Yifeng’s blog post "Blockchain Introductory Tutorial". I would like to thank this great master for his popular science.
2. Due to limited space, the knowledge about Merkle Tree and asymmetric encryption has not been discussed in detail for the time being. Interested friends can check the information for further study.
9. A beginner’s guide to investing in digital currency (blockchain), just read this article
The entry threshold for blockchain and digital currency investment is relatively high compared to other investment methods. Many friends want to invest in digital currencies but don’t know where to start or what to learn. Although 51coins has updated a lot of relevant knowledge in the "Beginners Playing Coin" section, it is not systematic enough
This time we will systematically organize the information related to blockchain and digital currency investment. In summary, let everyone understand and invest in digital currency faster and more conveniently
1. Understand the blockchain and digital currency
No matter what you invest in, you must understand it. The same goes for blockchain and digital currencies. There are many introductions about blockchain on the Internet, some are too profound, and some are not comprehensive enough. I personally think the video "100 Questions on Blockchain" produced by Huobi is better
100 videos , all of which are blockchain-related knowledge, including: the birth of Bitcoin, operating principles, blockchain FAQs, mining, wallet introduction, etc., and are all in the form of animated videos, making it easier for everyone to understand. Although the explanation is not detailed enough, it can give you a preliminary understanding of digital currency and blockchain
2. Choose a trading platform
After understanding digital currency, you can try to use the trading platform Purchase a small amount of digital currency and experience the process. The purchase and sale of digital currencies must be completed through a trading platform, which is equivalent to a stock exchange in the stock market. It is recommended to choose a large trading platform for the trading platform, which has a comprehensive range of currencies, convenient transactions, and guaranteed fund security
The following three platforms are recommended: Binance, Huobi, and OKEX (ranked in no particular order)
< p> 3. Choose a walletIf digital currency is compared to cash, a wallet is equivalent to a bank card, used to store digital currency. There are many types of wallets, and the most commonly used ones now are mobile APP wallets (light wallets). Wallets are also divided into types. Different similar digital currencies cannot be transferred to the same wallet. For example: imtoken is Ethereum money.package, then it can only store Ethereum and tokens issued based on Ethereum, but not other currencies
There are also wallets that claim to support all digital currencies, but most of these wallets are not yet complete.
Of course, after we buy digital currency, we don’t need to deposit it in the wallet, but directly put it in the exchange account, which can save the handling fee and not be so troublesome. Large exchanges such as Huobi and OKEX are relatively It is safe. I personally basically put digital currencies on exchanges
4. Determine the investment plan
Before investing in digital currencies, we must first determine our investment plan and plan to invest. How much money, how much loss you can accept, what is the expected return, and how long the investment time frame is, determine it before investing. Digital currency is a high-risk, high-yield investment product. In the novice stage, you can invest only your spare money that does not affect your life. There is no limit on the amount of investment, and the minimum investment is a few hundred yuan.
Wait until you truly understand the market before making the appropriate investment. Increase the investment amount, but remember to keep the investment amount within your tolerance
5. Select the investment currency
After selecting the trading platform and confirming the investment plan, you can purchase Digital currency, so which one should we buy among so many digital currencies? When buying coins for the first time, it is recommended to choose mainstream coins. You can choose a few coins that you like among the top 20 in the market or recognized value coins
Find out what these coins are for and whether they are available What is the actual value, what news has recently affected the currency price trend, etc.
Understand these issues before buying, and be sure to pay attention to the purchase price before buying
6. Common tools, Website
1. Non-small account: You can view information related to each currency and exchange, including currency price, historical price, increase and decrease, circulation volume, ranking and other information
2 , AICoin: The function is similar to that of non-small accounts. The K-line of aicoin is very convenient and easy to use. It is the first choice for watching K-line charts
3. Coin World: Real-time updates of news and information related to various blockchains and digital currencies
4. Golden Finance: A relatively comprehensive blockchain media platform, including news, news, quotes, celebrity columns, etc.
7. Learn more relevant knowledge
< p> With the above 6 points as a basis, even if we have initially learned about digital currency investment, we still need to learn more knowledge if we want to truly make money by investing in digital currencies. The two most important points are to deepen the understanding of blockchain and technical analysis (K line)These two are too broad and cannot be learned overnight, so I will not introduce them, K You can find a lot of online knowledge online. As we invest longer, understand more currencies, and come into contact with more related matters, we will gradually deepen our understanding of blockchain.
