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foreword
The previous blockchain article introduced the birth of blockchain and the underlying operating principles. This article mainly introduces the development of blockchain applications and further understands blockchain.
The arrival of Ethereum
Ethereum was proposed by Vitalik (V God) in 2013 and launched in 2015. The positioning of Ethereum in the white paper of Ethereum is: a decentralized application platform based on blockchain technology, relative to Bitcoin: As a peer-to-peer electronic cash system, the applications supported by Ethereum are not limited to payment transactions. Because of the arrival of Ethereum, the application ecology of the entire blockchain industry has slowly expanded from a single digital currency transaction to more and more application scenarios, and the qualitative nature of blockchain technology has also been broadly extended from distributed ledger technology. The chain has also spanned from the 1.0 era to the 2.0 era.
The biggest difference between 2.0 and 1.0 is that 2.0 is Turing complete and supports the realization of various applications in the form of smart contracts.
What is Turing Complete?
First of all, Turing was a British mathematician and scientist, known as the father of computer science and the father of artificial intelligence. The Turing machine he proposed is to allow a virtual machine to replace human paper and pen to perform mathematical operations. Turing completeness means that a series of rules for operating data can simulate any Turing machine. These rules can be an operating system in the computer field, a programming language, or a virtual machine. For example, in the JVM, programs written in Java can be run script. The basis for satisfying Turing's completeness is the need to have branching capabilities, that is to say, you can go to any location to calculate, and at the same time, you need to meet the capacity (memory) required for calculation. This memory also serves as a limit. Imagine if there are infinite There may be an infinite loop in the capacity calculation at the same time, so it will not know whether the program is calculating normally. In general, blockchain 2.0 has become an operating system or virtual machine that can write programs.
What is a smart contract?
Let’s understand non-smart contracts first. For example, when we borrow money from banks or individuals, we need to sign a loan contract or pay an IOU. If we don’t pay back when it’s due, the bank can go to FY to sue, and then the law FY will force you to repay money. In the middle, FY, as a trusted third party, assists in guaranteeing the execution of the contract, which we can understand as a non-smart contract.
Through smart contracts, no third party is required to guarantee the execution of the contract. Its essence is to write a series of automatically executed codes on the blockchain, and automatically repay when it expires or mortgage it with collateral. Smart contracts were proposed in 1990, but they lack a trusted execution environment, and the blockchain can provide trusted execution for the operation of smart contracts, because smart contracts run on the blockchain, which can guarantee the contract and execution results are not modified. In Ethereum, smart contracts can be written based on JavaScript and Solidity programming languages, and run on EVM (Ethereum Virtual Machine).
Applications of Ethereum
Since smart contracts have the advantages of automatic execution, openness, transparency, non-tampering, security, etc., their applications are also relatively extensive. They can be based on decentralized applications (DApps) coded by smart contracts, and can also issue tokens based on smart contracts.
Decentralized application DApp
After the launch of Ethereum, DApps became popular all over the Internet. Obsessed with cats is an early representative. Up to now, there have been thousands of DApps, including games, finance, media and other categories. At present, the best decentralized application developed on Ethereum is the financial category, also called decentralized finance (Defi). Whether it is payment, lending or trading, traditional finance requires the intervention of various intermediaries, and cumbersome procedures are required for borrowing and mortgages. On the other hand, centralized finance eliminates the third party, cumbersome procedures and transaction costs of traditional finance. The payment does not depend on the bank's account system, but peer-to-peer payment, which is especially convenient in the scenario of cross-border payment; mortgage assets do not need to be mortgaged to borrow money Banks, but with the openness, transparency and non-tampering characteristics of the blockchain, assets are mortgaged on the blockchain, and all major exchanges have this business model.
token issuance
Currency issuance was also popular across the Internet. In the blockchain 1.0 era, if an exchange wants to issue a transaction currency like Bitcoin, since the source code of Bitcoin is open, it only needs to modify some parameters to issue the currency. The arrival of Ethereum makes it easier to issue currency, based on the ERC20 protocol (which defines some interface standards), and then an ERC20 token (Token) can be issued by writing an asset by writing a smart contract. The transaction records of these Tokens It will be recorded on the Ethereum blockchain. Miners on the entire network will not only monitor ETH, but also monitor these Tokens. At the same time, ETH and these tokens can also be exchanged. Because the code of the token issuance has templates for reference, the technical threshold is relatively low, so many speculators sell RZ at a low price after issuing tokens, and "cut leeks" after being circulated on the exchange. This is also the notorious before. ICO is now expressly banned.
Public Chain & Consortium Chain
In addition to the two blockchain projects of Bitcoin and Ethereum, there is also the currency issued by modifying several parameters of the Bitcoin source code mentioned above. This currency has no innovation, and we call it "altcoin". The representative is Litecoin. In addition, there is Grapefruit Coin (EOS) represented by the DPos consensus mechanism. The goal of EOS is to realize the design of a blockchain system that can carry commercial applications. We know that the performance of Bitcoin and Ethereum is very low, and it is not suitable for online shopping. In the business scenario of hundreds of thousands of TPS, EOS can carry 4,000 TPS, and there is no transaction fee, and the community is also well-known (the local digital currency team Wenzhou re-invested in EOS).
In addition to public chain projects such as Bitcoin, Ethereum, Litecoin, and Yuzu Coin, there is also an alliance chain. The biggest difference between the two is that the alliance chain does not issue coins, has no reward mechanism, and requires the permission of an organization to join a node. The most well-known alliance chain project should be Hyperledger, an open source project initiated by the Linux Foundation, based on which developers can build alliance chains to meet different business scenarios. The well-known one in China is Ali’s Ant Blockchain, which is used in financial scenarios, retail scenarios, and life scenarios.
Summary of Blockchain Applications
The bottom layer is based on the blockchain technology and has derived a lot of applications and industries. For example, the blockchain browser can help users directly query the transaction status, and the wallet can help users transfer funds directly based on the chain instead of the exchange; because block rewards The mechanism gave birth to the mining industry (which has been expressly prohibited), and of course the initial application of the exchange; after the birth of Ethereum, applications such as Defi and NFT digital assets based on smart contracts appeared; and now the relatively popular operation The "decentralized" Internet Web3.0 based on the "block chain" technology.
In addition, the integrated application of blockchain technology plays an important role in new technological innovation and industrial transformation, and more industries are involved. Breakthrough, accelerate the development of blockchain technology and industrial innovation", a certain FY has been identified as a blockchain pilot unit. I believe that in the near future, the blockchain will create broad prospects and burst out with great potential.
