用以太坊开发区块链的公司,以太坊搭建区块链开发

请查看相关英文文档

⑴ Blockchain and smart contracts, Ethereum development, compiled by 183 developers, summary of knowledge system

Available tools and components for developing applications on Ethereum, Guidelines for modes and platforms.

The creation of this list was driven by product managers at ConsenSys who saw a need for better sharing of tools, development patterns, and components between new and experienced blockchain developers.

Develop smart contracts

Smart contract language

Architecture

IDE

Other tools

< p> Test the blockchain network

Test the Ethereum faucet

Front-end Ethereum API

Back-end Ethereum API

Bootstrap/Out-of-the-Box Tools

Ethereum ABI (Application Binary Interface) Tools

Ethereum Client

Storage

Mahuta - IPFS storage service with additional search capabilities, formerly known as IPFS-Store

OrbitDB - decentralized database on top of IPFS

JS IPFS API - Client library for the IPFS HTTP API, implemented in JavaScript

TEMPORAL - Easy-to-use API to IPFS and other distributed/decentralized storage protocols

PINATA - Using The Easiest Way to IPFS

Messaging

Testing Tools

Security Tools

Monitoring

Other Miscellaneous Tools

Cheshire - A native sandbox implementation of the CryptoKitties API and smart contracts, available as a Truffle Box

ERCs - Ethereum comment request repository

ERC-20 - Original token contract for fungible assets

ERC-721 - Token standard for non-fungible assets

ERC-777 - Improved token standard for fungible assets

ERC-918 - Mineable Token Standard

Popular smart contract libraries

Scalability

Payment/State Channels

Plasma

Sidechains< /p>

POA Bridge

POA Bridge User Interface

POA Bridge Contract

ZK-SNARK

ZK-STARK < /p>

Pre-built UI components

The above content is from the git library:

github.com/ConsenSys/ethereum-developer-tools-list

< p> I am Yu Ge, a full-stack programmer starting a business in Shenzhen, focusing on blockchain, metaverse and smart contracts, as well as additional small programs and app development.

[Prayer]

⑵ Introduction to Ethereum

How to buy ETH?

How to buy ETH with credit/debit card?

Binance (in the case of currency exchange) allows you to purchase ETH seamlessly through your browser. Operation steps:

You can also buy and sell ETH in the P2P market. You can buy tokens from other users through the mobile app Shannian Coin. Here are the steps:

Unlike Bitcoin, Ethereum is not just for cryptocurrency networks. It can also be used to build decentralized uses, and Ether, as a tradable token, has become the fuel of the ecosystem. So the main function of Ether is to provide power to the Ethereum network.

Not only that, Ether can be used to purchase goods and services like other traditional currencies.

Heat map of retailers accepting ether as a payment method

People can use Ethereum’s native currency, ETH, as digital currency or collateral. Some people also regard ETH as a store of value like Bitcoin. But it is different from Bitcoin because the high programmability of the Ethereum blockchain gives ETH more utility. It also means that Ether has become the source of vitality for decentralized financial applications, decentralized markets, exchanges, games and other applications.

ETH is not based on any bank, which means you will be responsible for your own funds. You can store your tokens on exchanges or in your own wallet. But remember, when you use a wallet for self-protection, be sure to keep the mnemonic securely so that if you lose access to the wallet, you can recover your money.

Once data is added to the Ethereum blockchain, it can hardly be changed or deleted. This means that the destination address and amount of funds to be sent must be carefully checked before the transaction is fixed (before the trading order is issued). When remitting large amounts, it is best to remit small amounts to the address for address confirmation.

Due to the smart contract being hacked, Ethereum decided to reverse malicious transactions in 2016Forced to hard fork. However, this reversal is only an extreme measure for special events and is not the norm.

All transactions added to the Ethereum blockchain are visible to the public. Even if your real name is not shown on an Ethereum address, observers will determine your identity through other methods.

Since ETH is not a stable asset, it may cause you gains and losses. Some people choose to hold ether for the long term, betting that the network will become a global programmable settlement layer in the future. Others choose to use ether to trade with other Altcoins (counterfeit coins). Both strategies also have their own financial risks.

As a mainstay of decentralized finance (DeFi), ETH can also be used to lend, serve as collateral for loans, mint synthetic assets, or as a bet on the future.

Some investors may invest in Bitcoin for the long term and do not include other digital assets in their portfolios. Some investors are more flexible, mixing ETH and other fake coins in their portfolios, or using a certain percentage of their funds for short-term trading (such as day trading or swing trading). There is no universal way to make money in the market, and every investor must choose the strategy that best suits him based on his actual situation.

There are many ways to store tokens on the market, and each method has its advantages and disadvantages. Like anything else that is risky, the best way to choose is to diversify among the options available. Tonghe

Typically, storage solutions are either managed or unmanaged. A custody solution means you can entrust your funds to a third party (such as an exchange). At this time, you need to log in to the custodian platform to trade crypto assets.

A non-custodial solution is just the opposite: 3354 uses a cryptocurrency wallet to manage funds. Crypto wallets do not hold coins like physical wallets, but instead provide cryptographic keys that allow you to access your assets on the blockchain. Remember: When using a non-custodial wallet, always back up your mnemonics!

If you want to deposit ether on an exchange, please follow the steps below:

You need to deposit ETH into an exchange account to facilitate various trading activities. Storing ETH on Binance is easy and secure. The Binance ecosystem also allows you to earn income through loans, job rebates, airdrop promotions, and sweepstakes.

If you want to withdraw ETH from your exchange account, you need to follow these steps:

If you want to store ETH in your wallet, then there are two options: hot wallet and cold wallet.

Cryptocurrency wallets that are connected to the Internet in some way are called hot wallets. It is usually a mobile or desktop application and allows you to check your balance, or send and receive tokens. Because the hot wallet is connected to the Internet, it is easy to be attacked, but it is very convenient for people's daily use. Trust Wallet is a mobile wallet that supports multiple currencies.

A cold wallet is a crypto wallet that is not exposed to the Internet. Because there are no network attack vectors, the probability of being attacked is significantly reduced. However, cold wallets are not as portable and easy to use as hot wallets. Both hardware wallets and paper wallets are cold wallets. There are very few nowSomeone is using an outdated and risky banknote bag.

For details on the classification of crypto wallets, please see "Interpreting Crypto Wallet Types".

Vitalik Buterin designed the original Ethereum pattern. It consists of two rotating sum symbols (the Greek alphabet for the horse). Ethereum’s final logo (based on this pattern) was surrounded by a rhombus (called an octahedron) and four triangles. Similar to other cryptocurrencies, Ethereum is composed of standard Unicode symbols, so the price of Ethereum can be easily displayed in applications and websites. Just like the U.S. dollar uses the symbol $, the symbol used by Ethereum is

Related questions and answers: What does Ethereum mean?

Ethereum (ETH) is a digital token of Ethereum. Like other digital currencies, Ethereum can be bought and sold on the trading platform. However, due to the recent instability in currency prices, few people speculate in currencies now! But you don’t have to only speculate to get the virtual currency ETH. You can also get it through mining. Salmon miners can quickly obtain Ethereum, so you can quickly understand what Ethereum is!

⑶ What is Ethereum? A Beginner’s Guide to Ethereum Development

What is Ethereum? A Beginner’s Guide to Ethereum Development
Many students are already eager to join the blockchain development team I came here, but I feel like I don’t know where to start. This article will be based on the Ethereum platform and introduce the obscure concepts involved in Ethereum development in a popular way, so that you can easily get started.
What is Ethereum
Ethereum is a decentralized application platform built on blockchain technology. It allows anyone to build and use decentralized applications running on blockchain technology within the platform.
For students who don’t understand this sentence, you can temporarily understand that Ethereum is Android in the blockchain. It is a development platform that allows us to write applications based on blockchain technology just like the Android Framework.
Before there was Ethereum, writing blockchain applications was like this: copy a copy of the Bitcoin code, and then change the underlying code such as encryption algorithm, consensus mechanism, network protocol, etc. (This is the case for many altcoins. A new coin will come out if you change it).
The Ethereum platform encapsulates the underlying blockchain technology, allowing blockchain application developers to develop directly based on the Ethereum platform. Developers only need to focus on the development of the application itself, thus greatly reducing the difficulty.
At present, a relatively complete development ecosystem has been formed around Ethereum: with community support, there are many development frameworks and tools to choose from.
Smart Contract
What is a Smart Contract
The program on Ethereum is called a smart contract, which is a collection of code and data (state).
Smart contracts can be understood as contracts (special transactions) written in code that can be automatically executed on the blockchain (driven by events).
In Bitcoin Script, we have mentioned that Bitcoin transactions can be programmed, but Bitcoin Script has many restrictions and the programs that can be written are also limited, while Ethereum is more complete (in computer science terms , call it "Turing complete"), allowing us to write programs (smart contracts) that can do almost anything just like any high-level language.
Smart contracts are very suitable for application scenarios that require high trust, security and durability, such as: digital currency, digital assets, voting, insurance, financial applications, prediction markets, property ownership management, Internet of Things, peer-to-peer transactions, etc. wait.
At present, apart from digital currency, there are not many real-life applications (just like the mobile platform has just begun to come out). I believe that within 1 to 3 years, various killers will slowly appear.
Programming language: Solidity
The default programming language for smart contracts is Solidity, and the file extension ends with .sol.
Solidity is a language similar to JavaScript. It is used to develop contracts and compile them into Ethereum Virtual Machine byte code.
There is also a smart contract development language that looks like Python: Serpent, but it is recommended that you still use Solidity.
Browser-Solidity is a Solidity IDE for browsers. You can click in to have a look. We will introduce more articles about the Solidity language in the future.
Operating environment: EVM
EVM (Ethereum Virtual Machine) Ethereum Virtual Machine is the operating environment for smart contracts in Ethereum.
Solidity is to EVM just like it is to JVM, so it will be easy for everyone to understand.
The Ethereum Virtual Machine is an isolated environment, and the code running inside the EVM cannot have any contact with the outside world.
The EVM runs on the Ethereum node. When we deploy the contract to the Ethereum network, the contract can run on the Ethereum network.
Contract Compilation
The Ethereum Virtual Machine runs the bytecode form of the contract, which requires us to compile the contract before deployment. You can choose Browser-Solidity Web IDE or solc compiler.
Contract deployment
When developing applications on Ethereum, the Ethereum client (wallet) is often used. Usually when we are developing, we generally do not come into contact with the concept of client or wallet. What is it?
Ethereum client (wallet)
Ethereum client, in fact, we can understand it as a developer tool, which provides account management, mining, transfer, deployment and execution of smart contracts, etc. Function.
EVM is provided by the Ethereum client.
Geth is a classicA client used when developing Ethereum, developed based on the Go language. Geth provides an interactive command console, which contains various functions (API) of Ethereum through the command console. We will introduce the use of Geth in an article later, but here everyone has a concept.
The Geth console is similar to the console in the Chrome browser developer tools, but it runs in the terminal.
Compared to Geth, Mist is an Ethereum client with a graphical operation interface.
How to deploy
The deployment of smart contracts refers to publishing the contract bytecode to the blockchain and using a specific address to identify the contract. This address is called a contract account.
There are two types of accounts in Ethereum:
· External accounts
This type of account is controlled by a private key (controlled by a person) and is not associated with any code.
·Contract Account
This type of account is controlled by their contract code and has code associated with it.
Unlike Bitcoin’s UTXO design, Ethereum uses a simpler account concept.
Both types of accounts are the same for EVM.
The difference and relationship between external accounts and contract accounts is this: an external account can send messages to another external account or contract account by creating and signing transactions with its own private key.
Sending a message between two external accounts is the process of transferring value. But messages from the external account to the contract account activate the code of the contract account, allowing it to perform various actions (such as transferring tokens, writing to internal storage, mining a new token, performing some operations, creating a new contract, etc. wait).
Only when the external account issues instructions, the contract account will perform the corresponding operation.
Contract deployment is to deploy the compiled contract bytecode to the Ethereum blockchain in the form of sending transactions through an external account (the actual deployment is successful only after the actual miner produces the block).
Run
After the contract is deployed, when you need to call the method of this smart contract, you only need to send a message (transaction) to this contract account. After the message is triggered, the code of the smart contract will be executed in the EVM. .
Gas
Similar to cloud computing, the resources that occupy the blockchain (whether it is a simple transfer transaction or the deployment and execution of a contract) also require corresponding fees (there is no free lunch in the world, right? ).
Gas mechanism is used for billing on Ethereum. Gas can also be considered as a workload unit. The more complex the smart contract is (the number and type of calculation steps, the memory occupied, etc.), the more it requires to complete the operation. Gas.
The amount of Gas required to run the contract for any particular contract is fixed and is determined by the complexity of the contract.
The Gas price is stipulated by the person running the contract when submitting the request to run the contract to ensure thatDetermine the fee he is willing to pay for this transaction: Gas price (denominated in Ethereum) * Gas ​​amount.
The purpose of Gas is to limit the amount of work required to execute a transaction while paying for execution. When the EVM executes a transaction, Gas will be gradually consumed according to specific rules. No matter where it is executed, once the Gas is exhausted, an exception will be triggered. All state modifications made in the current call frame will be rolled back. If there is Gas remaining at the end of execution, these Gas will be returned to the sending account.
Without this restriction, someone would write a contract that cannot be stopped (such as an infinite loop) to block the network.
So actually (to put the previous content together), we need an external account with an Ethereum balance to initiate a transaction (ordinary transaction or deploy and run a contract). When running, the miner charges the corresponding work Quantity fee.
Ethereum Network
Some anxious students may want to ask, how can we develop smart contracts without Ethereum? You can choose the following methods:
Select the Ethereum official website test network Testnet
In the test network, we can easily obtain free Ether coins. The disadvantage is that it takes a long time to initialize the node.
Use a private chain
Create your own Ethereum private test network, often called a private chain, which we can use as a test environment to develop, debug and test smart contracts.
With the Geth mentioned above, it is easy to create your own test network. You can mine as much Ethereum as you want without having to synchronize the entire blockchain data of the official network.
Using the Developer Network (Mode)
Compared with the private chain, under the Developer Network (Mode), a developer account with a large balance will be automatically allocated for us to use.
Use simulation environment
Another way to create a test network is to use testrpc. testrpc is an Ethereum environment simulated locally using memory. It is more convenient and faster for development and debugging. And testrpc can help us create 10 test accounts with funds at startup.
When developing a contract, you can test it in testrpc and then deploy it to the Geth node.
Update: testrpc has now been integrated into the Truffle development framework and is now named Ganache CLI.
Dapp: Decentralized Application
The Ethereum community calls applications based on smart contracts decentralized applications (DecentralizedApp). If we understand the blockchain as a database that cannot be tampered with, and smart contracts as programs that deal with the database, then it is easy to understand Dapp. A Dapp not only has smart contracts, but also needs a friendly user interface and other things.
Truffle
Truffle is a Dapp development framework. It can help us deal with a lot of trivial things, allowing us to quickly start the process of writing code - compiling - deploying - testing - packaging DApp.
Summary
Let’s summarize now. Ethereum is a platform that allows us to easily use blockchain technology to develop decentralized applications. In this application, Solidity is used to write and blockchain Interactive smart contracts, after the contract is written, we need to use the Ethereum client to deploy and run the contract with an account with balance (using the Truffle framework can better help us do these things). For the convenience of development, we can use Geth or testrpc to build a test network.
Note: In order to make it easier for everyone to understand, this article makes analogies to some concepts. Some of them are not strictly accurate. However, I also think that for beginners, it is not necessary to master every concept in detail and accurately. Learning is A gradual and in-depth process, many times we will find that after a period of time, we will have different understandings of the same thing.

⑷ What technology development is needed for blockchain?

What technology development is needed for blockchain:
1. Blockchain theory: Blockchain developers must understand the blockchain Theoretical knowledge and familiarity with it are the most basic requirements for a blockchain developer. The content includes blockchain network architecture, decentralization and other related application technologies. Expanding technical theory is mastery of Ethereum development.
2. Smart contract: Smart contract is a string of codes that blockchain developers need to write in blockchain programming language. It is a trust mechanism developed after imagining logic according to different scenarios, aiming to eliminate the intervention of third parties. Create an efficient and high-trust blockchain network. Blockchain developers need to realize automatic execution of this string of code, and the operation effect is irreversible.
3. Cryptography: Many blockchain application scenarios have high encryption, and point-to-point encryption mode is a characteristic of cryptography. By studying cryptography, blockchain developers understand encryption concepts such as wallets, keys, and a wide range of encryption and decryption technologies
4. Distributed architecture: Blockchain developers must understand the functions of distributed architecture and networks . Decentralized network is the foundation of the blockchain architecture. The transmission of information in the blockchain network must follow a decentralized approach so that everyone can enjoy the same network rights.

⑸ What is Ethereum? What is the relationship between Ethereum and the blockchain?

What is Ethereum:

Ethereum is a technology based on Bitcoin and concepts applied to computer innovations. Ethereum itself imitates many of Bitcoin's technologies to maintain the computer platform. Blockchain technology is one of them.
The Ethereum platform can safely run any program that users want.

Advantages of Ethereum over other competitive currencies

EthereumBefore its emergence, there were already some digital currencies that imitated Bitcoin. However, these projects themselves have certain shortcomings and can only support one or several specific applications at the same time. (A better digital currency trading platform is in "Bihui")

However, the reason why Ethereum can surpass the limitations of these previous projects is because of the core idea of ​​Ethereum.

What Ethereum wants to implement is a blockchain protocol with a built-in programming language. Since it supports programming languages, theoretically any blockchain application can be defined in this language and then serve as a An application that runs on the Ethereum blockchain protocol.

Ethereum is designed to be very flexible and adaptable.

Ethereum aims to combine the strengths of blockchain technology in order to add the advantages of blockchain, such as decentralization, openness and security, to almost all computing fields. .

Ethereum’s blockchain applications

Ethereum has many blockchain applications, such as gold and stock digital applications, financial derivatives applications, DNS and digital Certification and more.

Ethereum has been implemented by many startup companies in more than 100 blockchain applications.

Ethereum has also been closely followed by some financial institutions, banking consortiums (such as R3), and large companies like Samsung, Deloitte, RWE and IBM, which has also spawned a number of projects such as Simplification and automated financial transactions, merchant loyalty index tracking, gift cards designed to decentralize electronic transactions, and other blockchain applications.

The relationship between Ethereum and blockchain:

Ethereum is a programmable blockchain.

Ethereum does not give users a series of preset operations (such as Bitcoin transactions), but allows users to create complex operations according to their own wishes.

In this way, Ethereum can be used as a platform for many types of decentralized blockchain applications, including but not limited to cryptocurrency.

Like other blockchains, Ethereum has a peer-to-peer network protocol. The Ethereum blockchain database is maintained and updated by numerous nodes connected to the network. Each network node runs an Ethereum emulator and executes the same instructions. Therefore, people sometimes refer to Ethereum as the "world computer".

⑹ Please help, what currency is obc