Ethereum standard erc721
in order to create erc20 token, you need to write down the following contents
- token name
- token symbol
- token decimal
- number of tokens is in circulation
- Contract
- code verification source code
in addition to erc20, there are erc20, erc721, erc223, erc621, erc827, But for erc721, by the way, erc721 is a protocol mainly used for blockchain games. The blockchain games you often see are basically based on erc721
Ethereum is not only a database, it also allows you to run programs in the trusted environment of the blockchain. Ethereum has built a virtual machine named EVM (Ethereum virtual machine) on the blockchain. EVM allows code to be verified and executed on the blockchain, providing guarantee for code to run in the same way on everyone's machine. These codes are included in the smart contract. In addition to tracking the account balance, Ethereum uses the same method to save the EVM status on the blockchain. All nodes process the smart contract to verify the integrity of the contract itself and its output.
I think the first reason why Ethereum has been setting new records is that it has a lot of capital
the second reason is that many ordinary people have paid attention to virtual currency . These ordinary people have strong purchasing power, and they may have been speculators in stocks or funds before. When they find that the virtual currency is rising well, they will bring a lot of money into the market. The admission of these ordinary people will increase more capital admission, because in the view of capital, these ordinary people are a crop of leeks
the third reason is e to the soaring price of bitcoin, bitcoin is now rising very rapidly, from $20000 a bitcoin in 2020 to $60000 a bitcoin now. It's terrible. For a lot of capital, they can't speculate on bitcoin. Because bitcoin's plate is too big, they have to go back and speculate on Ethereum
first, a large amount of capital has entered the market
at present, the global economy is not very good, there are not many things that can be invested, and the global currencies are devaluing and inflating for a lot of capital, their money will depreciate one day if they hold it in their hands. They need to invest their money. At this time, they find that the virtual currency can keep the value and will not inflate. At this time, there will be a lot of capital, with a lot of money to buy Ethereum. When a lot of people go to buy Ethereum, it is normal for Ethereum prices to rise
with Ethereum officially confirming erc-721 as one of the new token standards, many people are asking what erc-721 is recently. There are many technical posts on the Internet to analyze the code differences between erc-721 and erc-20. They are very unfriendly to Xiao and leek. With the attitude of sharing knowledge, I will try to explain the most significant differences between erc-721 and erc-20 with intuitive words
erc-20 standard token:
1
2. It can be subdivided into N parts (n = 10 ^ 18)
conclusion: similar to the currency in real life, it can perform all monetary functions. The application cases are similar to legal currency and virtual currency
erc-721 standard token:
1
2. The minimum unit is 1 and cannot be subdivided
summary: non homogeneity exists widely in life, such as art, pets, handicrafts, custom-made items, etc., and can even be used to mark students in schools, doctors and patients in hospitals, etc. The application scenarios are very wide
the above description is relatively concise. Taking a look at specific projects can help you better understand erc-721 standard. At present, the popular projects using erc-721 standard can take a look at
- cryptokitties (cryptokitties | collect and breed digital cats!)
this is the "ethereal cat" mentioned before. It's very basic and interesting. Each cat is a token with unique attributes. The more unique the attributes, the higher the value of the cat. It's very popular, but its development potential is limited
- 0xcert (0xcert - supporting uniformity.)
this project is a recent project of personal interest, which is close to life and easy to implement. Erc-721 token is used to mark real-life artwork or a unique item, and record the basic attributes, characteristics, value, previous owners, etc. It is very helpful in combating counterfeits and piracy. It may also be used in the second-hand market, exchange of valuables and other scenarios in the future
personally, I am very optimistic about erc-721 standard. After the whole blockchain instry calms down from the carnival, the implementation of the project has become the first consideration for developers, and erc-721 is very suitable for connecting the blockchain with the real world.
Rc20 token standard (erc20 token standard) is a standard used to create token through Ethereum. According to the erc20 specification, a smart contract can be written to create a "interchangeable token". It is not mandatory, but following this standard, the token created can interact with many exchanges, wallets, etc. it has now been widely accepted by the instry
erc20 token standard was first proposed by Ethereum developer Fabian vogelsteller in the open source community. Later, Ethereum founder vitalik (known as "V God") wrote the first version of the document, which was called "standardized contract API" at that time_ Contract_ APIs
following erc20 token standard, smart contracts can be written. The token methods it needs to implement include: optional name, symbol, decimals, balance of, transfer, transfer from, approve, and allowance. The event responses it needs to implement include transfer, approve
in addition to erc20, Ethereum also focuses on erc721. Different from erc20, erc721 is a non fungible token standard (NFT)
The general syndromes oferc20 are interchangeable and homogeneous, while the general syndromes of erc721 are not interchangeable and heterogeneous; Erc20 can be subdivided infinitely, while erc721 can not be subdivided because its minimum unit is 1
in June 2018, erc721 was officially accepted by Ethereum community and became the final standard. The popular cryptokitties followed the erc721 standard
the Xueshuo innovation blockchain Technology Workstation of Lianqiao ecation online is the only approved "blockchain Technology Specialty" pilot workstation of "smart learning workshop 2020 Xueshuo innovation workstation" launched by the school planning, construction and development center of the Ministry of ecation of China. Based on providing diversified growth paths for students, the professional station promotes the reform of the training mode of the combination of professional degree research, proction, learning and research, and constructs the applied and compound talent training system