一张图区块链理解

❶What does blockchain mean?

Blockchain is a term in the field of information technology.

Essentially, it is a shared database. The data or information stored in it has the characteristics of "unforgeable", "full traces left", "traceable", "open and transparent" and "collectively maintained". . Based on these characteristics, blockchain technology has laid a solid foundation of "trust" and created a reliable "cooperation" mechanism, which has broad application prospects.

Blockchain is a new application model of computer technologies such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithm.

The Origin of Blockchain

Blockchain originated from Bitcoin. On November 1, 2008, a person claiming to be Satoshi Nakamoto ) published the article "Bitcoin: A Peer-to-Peer Electronic Cash System", which elaborated on the architectural concept of an electronic cash system based on P2P network technology, encryption technology, timestamp technology, blockchain technology, etc., which marked the The birth of coin.

Two months later, the theory came into practice, and on January 3, 2009, the first genesis block with serial number 0 was born. A few days later, block number 1 appeared on January 9, 2009, and was connected to the genesis block number 0 to form a chain, marking the birth of the blockchain.

❷ Popular explanation of what blockchain is

Question 1: What is blockchain? Can you explain the principle of 10-point blockchain in plain language: decentralization A distributed accounting system
The core of blockchain technology is that all currently participating nodes jointly maintain transactions and databases. It makes transactions based on cryptographic principles rather than trust, so that any two parties who reach an agreement can directly Payment transactions are carried out without the involvement of a third party.
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Technically speaking, a block is a data structure that records transactions, reflecting the flow of funds for a transaction. The blocks of transactions that have been reached in the system are connected together to form a main chain, and all nodes participating in the calculation record the main chain or part of the main chain. A block contains the following three parts: transaction information, hash hash formed by the previous block, and random number. Transaction information is the task data carried by the block, specifically including the private keys of both parties to the transaction, the number of transactions, the digital signature of electronic currency, etc.; the hash formed by the previous block is used to connect the blocks to realize the past The order of transactions; random numbers are the core of transaction completion. All miner nodes compete to calculate the answer to the random number. The node that gets the answer the fastest generates a new block and broadcasts it to all nodes for update, thus completing a transaction.
1.1 What is Blockchain
Blockchain (BlockChain) refers to a technical solution that collectively maintains a reliable database through decentralization and trustlessness. This technical solution mainly allows any number of nodes participating in the system toThrough a series of data blocks (blocks) generated using cryptographic methods, each data block contains all the information exchange data of the system within a certain period of time, and a data fingerprint is generated to verify the validity and link of its information (chain ) next database block.
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In layman’s terms, blockchain technology refers to a way for all people to participate in accounting. Behind all systems there is a database, which is a big ledger. Then who will keep this ledger becomes very important. At present, it is whoever owns the system who keeps the accounts. Each bank’s account books are kept by each bank, and Alipay’s account books are kept by Alibaba. But now in the blockchain system, everyone in the system has the opportunity to participate in accounting. If there are new transaction data changes within a certain period of time, everyone in the system can do accounting. The system will judge the person who has the fastest and best accounting during this period, write the recorded content to the ledger, and Send the contents of the ledger during this period to all other people in the system for backup. In this way, everyone in the system has a complete ledger. Therefore, this data becomes very safe. A tamperer needs to modify more than half of the system node data at the same time to truly tamper with the data. Such tampering would be extremely costly, making it nearly impossible. For example, Bitcoin has been running for more than 7 years. Countless hackers around the world have tried to attack Bitcoin, but so far there have been no transaction errors. It can be considered that the Bitcoin blockchain has been proven to be a safe and reliable system.
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1.2 Why is there blockchain innovation?
Human beings need to communicate during their activities, and communication is based on information. In the past, information circulation was not convenient enough to satisfy market participants. There is a demand for information, so intermediaries and centers are born. This centralized system has problems such as high cost, low efficiency, value dispersion, "information islands" and insecure data storage. However, due to technical and environmental factors, this system continued to operate for many years until the emergence of the Internet. The starting point of the first generation of the Internet is the TCP/IP protocol, which is an open code that implements a unified format for peer-to-peer transmission of information by all nodes on the network, and brings the basic values ​​of freedom and equality required by a global unified market into programmed, protocol-based, and reliably Execution. The Internet eliminates low-value, high-cost intermediate chains and achieves low-cost and high-efficiency global information transmission in a decentralized manner.
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However, the first generation of the Internet did not solve the problem of information credibility. Activities that can be decentralized on the Internet must be activities that do not require credit endorsement, and activities that require credit guarantee must be activities involving centralized third-party intermediaries. Therefore, Internet technology that cannot establish global credit has encountered great obstacles in its progress - people cannot participate in any value exchange activities on the Internet in a decentralized manner. To realize value exchange, people still need third-party intermediaries based on credit (such as banks, clearing agencies, exchanges). Global centralizationThe credit system still has problems such as high operating costs, low efficiency, and vulnerability to attacks and damage. For example, each country's legal currency has different credit values ​​and incompatible clearing systems, which adds a lot of cost to global trade.
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Therefore, what the second generation Internet must break through is: how to establish global credit in a decentralized manner? Let...>>

Question 2: What is blockchain? What does it mean in layman’s terms? What is China’s attitude towards blockchain? What can blockchain do? Blockchain, a great technology that accompanied the birth of Bitcoin, is currently being used in the financial field to significantly reduce transaction costs and improve efficiency, which is enough to excite Wall Street. However, this is just the tip of the iceberg. Its potential applications are very broad and will subvert every aspect of our lives in the future.
Blockchain is an important concept of Bitcoin. It is essentially a decentralized database and serves as the underlying technology of Bitcoin. One of the most basic characteristics of Bitcoin is decentralization. In recent months, financial giants have gradually begun to pay attention to Bitcoin's technology and used it in non-monetary fields, such as stock trading, election voting, etc. (1) Art Industry
Artists can use blockchain technology to declare ownership and issue numberable, 100% edition works in digital form for any type of artwork. It even includes a marketplace where artists can buy and sell through their website without the need for any intermediary services.
(2), Real estate industry
Use blockchain technology to solve various problems faced by everyone involved in real estate, including the naming process, land registration, agency intermediaries, etc.
(3), Insurance Industry
The financial industry has always been the most sensitive to advanced technology. Traditional banking and securities industry giants have been involved in the booming blockchain venture capital investment since 2014, with total global investment reaching US$1 billion within two years.
(4) P2P wallet
Personal assets can be traded through this P2P wallet in the future without going through any central institution, such as Bitcoin.
Most blockchains are in their infancy, mainly overseas. There are very few good domestic blockchain projects, so it is not recommended for any non-professionals to invest in blockchain projects. If you are very interested in blockchain technology and have a technical or financial background, it is recommended that you consider starting a business in this area. In terms of the blockchain protocol system, the lowest layer is the underlying technology of the blockchain, including the technical protocols of the blockchain, as well as some platform routing and basic algorithms; in the middle layer, some application interfaces and some credentials must be solved Issuance and verification, including some industry platform services, big data analysis, etc. This is a very rough classification, and there should be a more detailed classification.Law; the top ones are some applications of blockchain, including some financial applications and other applications, the Internet of Things, etc.
Introduction to Bubi Blockchain
Bubi Blockchain has been focusing on the research and development and innovation of blockchain technology and products since its establishment. It has a number of core technologies and has achieved substantial results in many aspects. Radical innovation has resulted in a number of core technological achievements, such as: mathematically provable distributed consensus technology, fast large-scale ledger access technology, multi-chain general ledger technology that supports business expansion, and interconnection technology between heterogeneous blockchains. wait. On April 25, "Gege Points" introduced the concept of blockchain into the points system, jointly opened it up with multiple parties, issued and redeemed points, and promoted the circulation of points. Each cooperative institution can jointly participate in transaction verification, ledger storage, and real-time settlement; the third-party payment platform of the enterprise points issuer makes the entry and exit of points more flexible. Bubi has developed its own basic blockchain service platform, which has been applied in equity, supply chain, points, credit and other fields. Bubi has been committed to building an open value circulation network with decentralized trust as the core, allowing digital assets to flow freely.
A simple understanding of blockchain is a technology at the bottom of Bitcoin, which is also a peer-to-peer electronic cash system that can realize peer-to-peer value delivery. We should distinguish between Bitcoin, Bitcoin blockchain, blockchain and blockchain. Blockchain technology and other concepts. In countries with relatively developed finance in the past, finance and blockchain technology have a long history, and the legislation of digital currencies and blockchain networks is also very important. With the advent of the financial era, large financial institutions are studying blockchain technology. They have their own teams and conceptual technologies. Slowly, banks in various regions are also participating in digital currency discussions. The application and support of this technology are not only that. The influence of blockchain on enterprises is also huge. For larger domestic enterprises, Bubi Blockchain is also used in various equity, supply chain, points and other fields. Major domestic financial institutions and enterprises have taken a fancy to the new industry. value, they have developed their own blockchain platforms, and blockchain has instantly become a new innovative industry in China. In terms of overseas internationalization, the United States has already obtained 15 blockchain patents at the end of last year compared to China. Blockchain financial applications are entering a new stage in an all-round way. Various applications will become more and more in-depth, and related changes will also become more and more profound. It has attracted more and more attention and will form a huge new trend... >>

Question 3: What is blockchain technology? What exactly is blockchain? What is blockchain? 1. Data blockchain is an important concept in the Bitcoin financial system. It records transaction record data on the entire Bitcoin network, and these data are shared by all Bitcoin nodes. Through the data block, we can query each transaction record. A look at the history of Bitcoin transactions. 2. Example: There are three persons A, B, and C. All funds of A and B are kept by C. And every financial transaction must be recorded by C. Now assume that A and B each have 1 million in custody of C. Then: A expenditure80,000 to B, then C’s account book record will subtract 80,000 yuan from A’s name, and add 80,000 yuan to B’s name. If B transfers 50,000 yuan to A, C will add 50,000 yuan to A's name and subtract 50,000 yuan to B's name in the account book. A spends 50,000 yuan to B, then C's account book record will subtract 50,000 yuan from A's name, and add 50,000 yuan to B's name. 3. The role of the data blockchain is similar to that of C’s account record book. It records the user’s ownership of Bitcoin and the records of all users’ Bitcoin transactions. It’s just that this “account record book” is recorded by the mining software of every Bitcoin miner on the network. If a Bitcoin transaction is confirmed by the data blockchain, the relevant information will be recorded in the data blockchain. Bitcoin’s “account record book” is called the data blockchain. All data blockchains on the network form Bitcoin’s distributed network database system. 4. The essence of data blockchain technology is a decentralized and distributed structure of data storage, transmission and certification methods. It uses data blocks to replace the current Internet's dependence on central servers, so that all data changes or transaction items are recorded. On a cloud system, the self-certification of data during data transmission is theoretically realized. In a far-reaching sense, this transcends the traditional and conventional information verification paradigm that relies on a center and reduces the cost of establishing global "credit." This point-to-point verification will produce a "basic protocol", which is a new form of distributed artificial intelligence and will establish a new interface and shared interface between human brain intelligence and machine intelligence.

Question 4: What is blockchain: This explanation of blockchain is more understandable. Blockchain refers to a technology that collectively maintains a reliable database through decentralization and trustlessness. plan.
In layman’s terms, blockchain technology refers to a way for all people to participate in accounting. There is a database behind all systems. You can think of the database as a big ledger. Then who will keep this ledger becomes very important. Currently, whoever owns the system keeps the accounts. Tencent keeps the accounts of WeChat, and Alibaba keeps the accounts of Taobao. But now in the blockchain system, everyone in the system has the opportunity to participate in accounting. If there are any data changes within a certain period of time, everyone in the system can do accounting. The system will judge the person who has the fastest and best accounting during this period, write his recorded content into the ledger, and record this Within a period of time, the contents of the ledger are sent to all other people in the system for backup. In this way, everyone in the system has a complete ledger. In this way, we call it blockchain technology.
Blockchain technology has become the darling of the financial community in China and has become a hot topic. Domestic Puyin Group has launched Puyin, a tea-based digital currency.

Question 5: Explain in an easy-to-understand manner what blockchain is. Blockchain can be understood as a database system in a sense.The development of blockchain can be divided into 1.0 and 2.0
1.0 is represented by Bitcoin, and its main application is virtual currency or digital currency application. The blockchain at this time can only be used for simple digital currency transactions.
2.0 is represented by the now popular ethereum (Ethereum) and the upcoming hyperledger. The blockchain at this stage can not only meet the corresponding digital currency transactions, but also use smart contracts to customize currency or asset transactions. If we use the database analogy, the emergence of smart contracts can be understood as allowing users to define functions or stored procedures in the database and call and execute them.
Different from traditional databases, the blockchain introduces consensus mechanism, incentive mechanism, p2p (network), hash and other specific elements, making it open, decentralized and non-tamperable. characteristic.

Question 6: What is blockchain? Can anyone explain it in simple terms? Blockchain is the underlying technology of Bitcoin. It is like a ledger that records all transactions. It is decentralized. What is decentralization? For example, when you buy something on Taobao, you place an order and pay in Alipay. Alipay will not transfer the money to the seller until you receive the goods. Alipay is the third party in that center. Without it, it means decentralization, just like buying things offline. If you pay with one hand and get the goods with the other hand, there is no third party.
The blockchain itself is a series of cryptographically related data blocks generated.
Look carefully to see if it looks like a ledger. The pieces one by one are blocks, and connected together they are the blockchain.
Many companies are developing this technology, including ours, and its prospects are incredible. For details, you can go to our official website and hope to adopt it, thank you

Question 7: What is blockchain technology? What is blockchain? How to explain the concept of blockchain? People in each industry have different understandings, and relevant explanations are gradually emerging due to more and more real-life applications. With the popularization of this blockchain technology, the related results are getting bigger and bigger. If we want to understand this technology, we must have an in-depth understanding of reality.
In the past six months, the concept of blockchain has gradually become popular in China, and a blockchain whirlwind has taken off in the financial circle. Blockchain has attracted the attention and favor of more and more people in the industry due to its unique technical advantages. Blockchain technology, which is decentralized (or multi-centered), highly transparent, cannot be tampered with, and has no single point of failure, is entering the field of vision of financial institutions and enterprises. It has at least been used in digital currency, payment exchange, registration and settlement, Digital assets, traceability and anti-counterfeiting, supply chain, Internet of Things and many other fields have moved from theoretical discussions to practical applications.
"Blockchain" was first introduced in early 2009 when "Bitchain" was released."Coin", blockchain has become the basic protocol and technical application for the launch, recording, and circulation of Bitcoin. Although Bitcoin has been controversial since its inception, it is still not even regarded as a "currency" by governments and monetary authorities. However, Bitcoin The blockchain technology used in currency has received widespread attention, including from governments and monetary authorities.
Why has blockchain become a rapidly heating up hot technology and topic?
This is the most important The most likely possibility is that Bitcoin, launched on the basis of blockchain technology, has opened up a kind of Internet user identity verification, wealth confirmation, and transaction that has little connection with traditional society (offline) and is fully applied in the online world (online). The exploration and attempt of new technologies and rule systems such as recording, notarization and verification, etc., provide people with optional paths and unlimited imagination to adapt to the development of the Internet society.
Judging from its application in Bitcoin, block Intuitively speaking, the chain is a set of new network blocks (BLOCK, also called communities) formed by combining encryption technology with Internet technology, setting up Bitcoin, configuring Bitcoin, verifying the identity of netizens, and mining Bitcoin. (Blockchain) confirmation, Bitcoin transaction records, and extended encryption of Bitcoin cross-block flows (value transfer) (adding factors such as block and transaction time marks) registration and verification, etc., Blockchain , that is, blockchain), fully encrypted, mutually authenticated Internet protocol rules and accounting (Ledger) system. Precisely because Bitcoin is not a substitute for offline legal currency, but is issued and managed by non-legal currency authorities, it is mainly Imitating the model of gold, a new, decentralized online currency (virtual currency) is completely protected and supported by basic Internet protocols and strict encryption technology. This also forms a set of laws that are different from and not subject to real society. A new currency rule and system, and can be bought, sold or exchanged with legal currency. Since Bitcoin was launched for more than 8 years, there has been no record of funds or user information being stolen. Its security has been verified, and its funds The efficiency and cost of clearing also have obvious advantages. This makes people's confidence in the blockchain technology used in Bitcoin continue to increase, and people are increasingly aware that although the blockchain was pioneered and pioneered by Bitcoin, A technology and protocol applied, but blockchain is not the same as Bitcoin, and its application will never be limited to Bitcoin. The application of blockchain can be decentralized or centralized. ; It can be a public chain model or a private chain model. Therefore, after Bitcoin, blockchain technology is also constantly developing and innovating, and constantly exploring new application fields, especially in the financial field.
The reason why blockchain is highly valued by more and more people is because the development and widespread application of the Internet have caused more and more economic exchanges and transaction activities to be conducted online, and the online world (or online society) It is rapidly expanding, enriching and active, and online transactions must solve the identity verification and value verification of the parties involved.Efficiency and security protection issues in transaction records, inspection and verification, etc. require strict intermediaries and agreements (rules or constitutions). In this regard, traditional thinking and customary practices are to follow the development trajectory of the transfer of offline transactions to online and push the common rules and practices of the real (offline) society to the online (network) society. However, in practice, it is increasingly It is difficult to adapt to the needs of online transactions.
For example, for the identity verification of the parties, the natural choice is to use the information on the identity documents protected by the laws of various countries as the basis, and then add account or transaction passwords, as well as facial recognition, iris, fingerprints and other biometrics to conduct online transactions. Verification, but this method first makes the citizen identity information in the cross-border interconnected online world subject to the administrative jurisdiction of real society... >>

Question 8: Easy to understand Explain clearly what is blockchain. The English name of blockchain is Blockchain. Block literally means block, block, and chain means chain, chain. Therefore, together they are translated into blockchain.
1. Use cryptography technology to encrypt and decrypt so that records cannot be tampered with. Common blockchain encryption methods include hash algorithm, RSA algorithm, elliptic curve algorithm, etc.;
2. The huge amount of calculation needs to be supported by a reasonable reward mechanism. Because every transaction must be recorded, Bitcoin’s blockchain has more than 60 gigabytes so far. Every new transaction requires confirmation of the information related to the trading account to ensure that the transaction is valid. The huge amount of calculation requires a computer with powerful computing power to complete.
In order to encourage the participation of powerful computing power, Bitcoin provides two rewards: one is to issue a certain number of Bitcoins to these computers every day; instead, all transfer fees are awarded to these computers. (The technical term for these computers is "mining machines", and the people who hold the mining machines are called "miners".)
Biying China is working hard on the digitization of assets and has launched the digital currency crowdfunding platform Biying China.

Question 9: What is the so-called "blockchain"? Blockchain itself is a tool called decentralization and trustlessness. For example, when you graduate from university, the current practice is to have a certificate recognized and issued by an authoritative agency as your certificate. This setting is more troublesome, because this is a piece of paper, and paper can be forged, so there will be various gaps. The issuing authority is also a person, and there will be various gaps in the middle. As long as it is related to people, whoever There are various possibilities related to media. The blockchain provides a great opportunity. As soon as you graduate, you will have a record on the blockchain. No one can change this record. This thing exists objectively. You, as a physical existence , and then as a data existence, the blockchain was born. In this case, if anyone wants to check where you graduated from, justIt's easy to solve this problem. This is similar to the big data often involved in social networking (WeChat) and payment platforms (Alipay, Yibao).

Question 10: What does blockchain mean? Regarding blockchain, I think you have already seen the concept on the Internet. Let me explain it based on my understanding!
First, let’s talk about its characteristics: 1. Openness and transparency 2. Decentralization 3. Anonymity 4. Information cannot be tampered with, eliminated 5. No trust cost
Blockchain is like a public ledger , everyone has the right to record and read, and everyone will jointly supervise to ensure its accuracy, and the recorded content will be permanently saved, and can only be added but not deleted! However, as the number of blocks continues to increase, costs will increase and efficiency will decrease. (I’m not sure whether technology can be used to make up for this. I hope someone who understands technology can point it out.)
Blockchain is divided into public chain, private chain, and alliance chain. Public chain: accessible to everyone, everyone has read and write permissions, completely open, transparent and decentralized. Private chain: Open to individuals or institutions, in which the owner of the private chain can set various permissions to make it partially centralized. Alliance chain: Open to specific organizations or groups, it is also "partially decentralized". According to the ledger at the beginning, members can view and transact, but cannot record and confirm bills, or require permission from the alliance. (The latter two do not have cost and efficiency issues)
Regarding blockchain, countries have begun to recruit talents in this area. For this, you can search online for "Central Bank Recruiting Digital Currency R&D Personnel". In addition, you can increase your understanding of blockchain by understanding its existing applications. What we usually refer to generally refers to public chains. Currently, those used abroad include Bitcoin, Ethereum and other domestic blockchains. Chain
1. Open and transparent: Every piece of data is verified by everyone and can be viewed by everyone at any time.
2. Decentralization: For example, when we shop on Taobao, we conduct transactions through the intermediary Taobao, and blockchain allows both supply and demand parties to directly contact each other for direct transactions through blockchain technology.
3. Anonymity: No personal privacy information is required to complete transactions on the blockchain, only your unique alphanumeric signature is required.
4. Information cannot be tampered with or deleted: Once the data has been verified and recorded, no one has the authority to modify it, let alone delete it!
5. No trust cost: The trust crisis in reality will not appear in the blockchain. Transactions in the blockchain do not require you to trust the other party. Only when both of you have enough "digital assets" to trade can it be carried out, and Under the supervision of the entire network, transactions will not be broken. If you have no idea about the cost of trust, just think about how many intermediaries there are in your city, or just think about Jack Ma, and you will know how big the cost of trust is.
I am still learning more about blockchain. I am Li Ailin. If you have any questions, you can discuss them together.,study together!

❸ What does blockchain mean and how to understand it

Blockchain is a new application model of computer technology such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithm.

Blockchain is an important concept of Bitcoin. It is essentially a decentralized database. As the underlying technology of Bitcoin, it is a series of related data generated using cryptography methods. Each data block contains a batch of Bitcoin network transaction information, which is used to verify the validity of the information (anti-counterfeiting) and generate the next block.

Notes

1. Blockchain Originated from Bitcoin, on November 1, 2008, a person claiming to be Satoshi Nakamoto published the article "Bitcoin: A Peer-to-Peer Electronic Cash System", which elaborated on P2P network technology, encryption technology, The architectural concepts of electronic cash systems such as timestamp technology and blockchain technology mark the birth of Bitcoin.

Two months later, the theory came into practice, and on January 3, 2009, the first genesis block with serial number 0 was born. A few days later, block number 1 appeared on January 9, 2009, and was connected to the genesis block number 0 to form a chain, marking the birth of the blockchain.

2. In order to realize the great leap forward development of blockchain finance, in order to promote the new development of China’s economy, accelerate the circulation of global assets, and realize the dream of rejuvenation that generations have been striving for, Puyin Group launched the On the 9th, a Puyin Blockchain Finance Guiyang Strategy Release Ceremony was held in Guizhou. At the meeting, the digital circulation of assets through blockchain, the blockchain financial transaction model, and the application of blockchain services and social public industries will be discussed. Explore.

❹ What is the concept of blockchain? Read it in three minutes!

On October 25, 2019, Xinwen Broadcast sent a very important signal: the country must vigorously develop blockchain. After that, blockchain has become an Internet celebrity, and the figure of "blockchain" is floating in the streets and alleys. In fact, many technology companies have already deployed blockchain technology.

Although blockchain is very popular, many people do not know much about blockchain.

What is blockchain?

Let’s first take a look at how Du Niang explained it. Network display: Blockchain is a new application model of computer technologies such as distributed data storage, point-to-point transmission, consensus mechanism, and encryption algorithms.

Why is blockchain called blockchain?

The blockchain is linked by blocks one by one, and the blocks are storage units one by one, which record the communication information of each block node. The blocks are much like the records of the database. Second-rateWriting data is creating a block. With the expansion of information exchange, one block continues with another, and the result is called a blockchain.

What are the characteristics of blockchain?

Blockchain mainly has the following characteristics:

1. Decentralization: In the blockchain system, every node has equal rights. and obligations, there is no central control here. Decentralization has well established trust relationships with each other. Although there is no central management organization, people can collaborate with each other and trust each other. This mainly applies blockchain distributed ledger technology.

2. Openness: Blockchain data is open to everyone. Except for some encrypted information that is not open, everyone can check the data here.

3. Independence: The entire blockchain system does not rely on other third parties. All nodes can automatically and securely verify and exchange data within the system without any human intervention.

4. Security: Blockchain has a certain degree of security and cannot be tampered with. Because everyone in the blockchain system has the same ledger, if someone wants to tamper with it, it is possible to forge a non-existent record only if they control more than 51% of the accounting nodes. Of course, this is basically impossible. This is mainly due to the core technology of the blockchain: the consensus mechanism. The consensus mechanism has the characteristics of "the minority obeys the majority" and "everyone is equal".

5. Anonymity: Many people think that if the blockchain is so open and transparent, will we lose privacy? In fact, no, although the transaction information in the blockchain is open and transparent, the identity information of the account is encrypted and can only be accessed with authorization.

Now let me tell you a story to help you better understand the blockchain.

There are three people in the family, mom, dad, older brother and younger brother. Last year, my father was in charge of the family's account books. He was responsible for all the family's income and expenses alone.

However, on the day of Double Eleven, my mother, who has always been frugal, wanted to buy herself a beautiful piece of clothing on a certain online store. When she checked the account book, she found something was wrong. It stands to reason that except for some money deposited in banks and financial management, the whereabouts of the daily consumption money at home are all in this account book, but no matter how you look at it, it is wrong. Some consumption is clearly not recorded, but is recorded.

Later, my father took the initiative to confess that he couldn’t help but buy a pack of cigarettes.

Later, my mother changed her strategy and the whole family kept accounts. Everyone recorded their monthly consumption expenditure in their own account books. Whenever there was a transaction or consumption at home, my mother would shout, "Book it," and everyone would record the transaction in their own books. This isIn the decentralized accounting model, everyone is the center and everyone has a ledger.

The previous accounting model for dad was centralized accounting. If dad wanted to do something alone, it would be difficult for anyone to see it. The decentralized accounting model has solved the problem of centralization very well. The disadvantage of bookkeeping is that it is very difficult for dad to tamper with the books.

For example, if dad wants to take some money from the ledger and secretly buy cigarettes, the amount of money is limited, and if he wants to take the money, he has to change the ledger, but he only tampered with his own ledger. No, he had to change the accounts of three people including himself. And this is undoubtedly more difficult than reaching the sky.

So, many times my father had the idea of ​​smoking, but he had no choice but to give up the idea due to the current situation.

Are blockchain and Bitcoin the same thing?

In fact, blockchain and Bitcoin are not the same thing. It is just the underlying technology of Bitcoin. Bitcoin is the first digital currency applied by blockchain.

In 2008, Satoshi Nakamoto first proposed the concept of blockchain. In the following years, it became a core component of the electronic currency Bitcoin, serving as a public account book for all transactions. Blockchain was first applied to Bitcoin.

The origin of blockchain is to solve the problem of trust, and one of the most successful applications of blockchain is digital currency. Bitcoin is arguably the most successful application of blockchain so far.

What are the applications of blockchain?

The application of blockchain is actually very wide. In addition to digital currency, the future applications of Bitcoin are still very extensive. Blockchain technology has been widely used in different industries. Such as product traceability, copyright protection and transactions, payment and settlement, Internet of Things, digital marketing, medical care, etc., promoting different industries to quickly enter the "blockchain+" era.

1. Payment and clearing: Blockchain can abandon the role of transit banks, realize point-to-point payment, reduce transit fees, and accelerate fund utilization.

2. Product traceability: For example, if we buy a piece of clothing on a certain store, we can see the past and present life of this piece of clothing.

3. Securities trading: Traditional securities trading requires the coordination of four major institutions, which is inefficient and costly. Blockchain technology can independently complete one-stop services.

4. Supply chain: Introducing blockchain technology into the supply chain system, synchronizing information within the system can control all links, better complete division of labor and collaboration, and facilitate subsequent accountability.

5. Intellectual property rights: With copyright on the chain, our photographic works, musical works, literary works, etc. will become our information, and the ownership of the information will be confirmed and become our property.

❺ ComicsIllustration What is Blockchain

Cartoon 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 do itThe 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, transaction The record information is also a string 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, whether the Hash that meets the requirements can be obtained depends entirely on the value of the random number. Miners must go through massive calculations and repeatedly generate random numbers in a general 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 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.
Let’s talk about the rewards for Bitcoin miners:
The Bitcoin protocol stipulates that miners who mine new blocks will receive rewards, which has been 5 since 2008.0 Bitcoin, 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.

❻ How to explain blockchain in a popular way

“Blockchain technology is considered to be the next generation of disruptive core technology after steam engines, electricity, and the Internet. If the steam engine unleashes People's productivity, electricity solves people's basic living needs, and the Internet has completely changed the way information is transmitted. Then the blockchain, as a machine that builds trust, will likely completely change the way value is transmitted in the entire human society."

I have just come into contact with the blockchain. There are too many basic knowledge that need to be understood and known. Don’t worry, today I will popularize this knowledge for you. Today, let’s first take a look at what public chains, private chains, alliance chains, and side chains are.

❼ A popular explanation of what blockchain is, and a picture to understand it

A popular explanation of what blockchain is, and a picture to understand it Understand blockchain

Blockchain is a hot topic recently. Many people are discussing blockchain issues. Recently, some domestic companies have begun to use blockchain technology to develop some products. , Blockchain is an underlying technology used in Bitcoin. This is because the popularity of Bitcoin has made many people pay attention to Bitcoin.But many people still don’t understand what blockchain is. Let me explain blockchain to me.

Bitcoin is a digital currency that many people are paying close attention to, and the underlying technology of Bitcoin is blockchain. Blockchain is a computer technology and a new application model. The blockchain is like a large database ledger, in which all transactions are recorded. The person who records this ledger is very different from traditional bookkeepers. Traditional bookkeepers are usually led by specialized bookkeepers. The accounting party performs the operations. For example, Taobao and Tmall are accounted for by Alibaba, and WeChat transactions are accounted for by Tencent. In the blockchain, all people participate in accounting. Everyone who participates in accounting has a ledger. .

Let me give you an example. For example, A wants to borrow 10,000 yuan from B. B wants to lend the money to A, but is worried that A will default on the debt after borrowing the money, so he will ask for a loan when borrowing money. A third-party notary helps B write down the account. This is the traditional accounting method, which relies on a third party to gain trust. The accounting books are in the hands of the third party. This kind of accounting There is the possibility of a third party tampering with the ledger, and decentralization means that there is no need for a notary when borrowing money, and there is no need to rely on a third party to gain trust. The decentralized situation is like when B lends money to A, B takes Using a loudspeaker, he shouted, "A asked me to borrow 10,000 yuan, please help me keep the account." At this time, everyone will take the account book in their hand and record the account. Everyone has an account book, and can Avoid the possibility of ledger tampering.

❽ What is blockchain? A cartoon to help you understand (a must-read for beginners)

The word "blockchain" was actually used in the early cryptography circles. The underlying technology of Bitcoin is called "Bitcoin". In English, Bitcoin starting with a capital B refers to the network system or network protocol of Bitcoin.

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 menA woman is like a chain. If a third party intervenes or she violates her partner, others can see it, and she 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.

❾ What is blockchain and how to simply understand blockchain technology

What is blockchain

Blockchain is through point-to-point transmission, A new technology that performs encryption algorithms. There are countless points in the blockchain. Each point represents a user. If a transaction occurs between points, the transaction record will be directly uploaded to the block. The data in the block will be uploaded according to time. Linked sequentially is a blockchain.

1. Blockchain is also called a distributed ledger. The ledger records the transaction records of all nodes. Each node needs to maintain the development of the blockchain, supervise whether the transactions are legal, and can also work together to Transaction testimony.

2. Encryption technology. The transaction information in the blockchain is public, but the personal information has been encrypted. There is no need to worry about the leakage of personal information. Only with the authorization of the individual can the other party Personal information is queried and the security of personal information is guaranteed.

3. Consensus mechanism. Every node in the blockchain trusts each other. Every user can trade with confidence because the data cannot be tampered with and every transaction must be legal and will not There is a possibility of fraud.

4. In scenarios where smart contracts and blockchain technology are applied, intelligent matching can be used. For example, insurance claims can be automatically settled.

How to simply understand blockchain technology

Blockchain technology can be understood in this way. Xiaohei and Xiaobai are both nodes in the blockchain. Borrowing 1,000 yuan is a transaction, and the data will be stored in the block. At this time, Xiaobai broadcasts to everyone that Xiaohei borrowed 1,000 yuan from him, and Xiaohei also broadcasts that he borrowed money from Xiaobai. He borrowed 1,000 yuan from Xiaobai. Everyone heard the news. On the repayment day, Xiaohei said that he had not borrowed 1,000 yuan from Xiaobai. At this time, everyone came out to testify to Xiaobai that Xiaohei had indeed borrowed money. 1,000 yuan.

In the above example, Xiao Hei and Xiao Bai are equivalent to the two nodes of the blockchain. Borrowing money is a transaction. As long as the transaction is made, transaction data will be generated and uploaded directly to the block. The data in the block is public. Not only can you see it, but everyone in the blockchain can see it. This ensures that Xiaohei will not breach the contract.If he says that he has not borrowed money, everyone in the block will supervise Xiaohei to repay the money, thus ensuring the legality of the transaction and mutual trust between each node.