25 lectures on basic knowledge of blockchain

1.

< Introction to cognition & gt Download link is attached at the end of the article)

new economy blueprint and guide

publication time: 2016

recommendation: this book is mainly for programmers. Combined with API programming, we can tell you the principle and usage of cryptocurrency, as well as how to develop related software. For non programmer readers, the first few chapters of this book are still applicable as in-depth introction of bitcoin. Book download

2.

blockchain is a kind of technology, which solves the core "trust" problem in the market economy and reces the trust cost between strangers to a very low level

there is one crucial thing in the market economy, which is "trust". Without trust, no deal can be established. When you go to LAICHANG to buy vegetables, if you don't believe that the pesticide content in vegetable is up to the standard, you won't trade with that dealer; If you buy a bottle of water in a small shop, the clerk will not sell you the water if he doesn't believe that the money you give is real

the traditional small-scale peasant economy is acquaintance economy, and the transaction scale is limited to people who are familiar with each other nearby. If an acquaintance deceives you, he will lose your social relationship and damage his reputation in the whole circle of acquaintances. We believe that acquaintances are less likely to cheat us than strangers

therefore, once we are beyond the scope of acquaintances, we need to use a high cost to identify whether a stranger will cheat me and how to avoid the risk of being cheated. This situation will hinder the transaction and restrict the transaction

in addition, different races, nationalities, cultures, religious beliefs and so on will naturally have this kind of trust problem

in the market economy, why can there be so many transactions between strangers? Because of the birth of a new mechanism to solve the problem of trust in strangers

so far, the most important mechanism to solve the trust problem is the "trust intermediary" organization and mode

as long as you and strangers trust a third-party organization, the trust problem between you can be solved through this third-party organization

this third-party organization, we call it trust intermediary. Both the government and the bank are trust intermediaries

you can sell the goods you have worked hard to proce to a stranger in exchange for a stack of RMB banknotes. It's because the credit of the note issuing bank and the guarantee of the authority of the government guarantee the currency value and effectiveness of the banknotes. Otherwise, sell things, in exchange for a few ordinary paper, who would like to

in the era of global village and Internet, the people who buy your things may be strangers who will not meet and thousands of miles away. Trust is lower, so Alipay assumes the role of trust intermediation. Buyers first pay the goods to Alipay's account. When they receive the goods, they confirm that they are OK, then they agree to sell the goods to the seller. Taobao and other e-commerce have been booming rapidly in just over ten years

trust intermediary is in a central position in the transaction system. All transactions should solve the trust problem through it

However, the cost of trust intermediary itself is often huge

as a trust intermediary, how much transaction tax does the government charge each year? What is the most profitable instry? Financial services. The annual profits of Alipay's ant suit are over ten billion. p> What does this mean? Both sides of the market actually pay a huge trust cost

if there is any way to cancel or greatly rece the trust cost, the transaction cost of the general public can be reced, and the profits can be greatly increased

so in the Internet era, blockchain technology is on the stage

it allows the trading party to get rid of the intermediary, solve the problem of trust among strangers, and greatly rece the cost of trust

the blockchain can be expanded on a large scale, the data is open and transparent, the data of each client is consistent, and even if some clients are destroyed, the data security will not be affected. These highly reliable technical features can solve the trust problem of strangers with low cost

this technology can be extended to all fields that can be digitized, such as digital currency, payment and clearing, digital bills, proof of rights and interests, credit reference, government services, medical records, etc

in the medium and long term, blockchain will be a revolutionary technology, which will bring about great social changes like the existing Internet, and has great investment value and money making opportunities

in the future, the companies that can combine blockchain with different scenarios to promote applications may be the next group of bat, the next Google, Microsoft and apple

as the first practical application of blockchain technology, bitcoin has been widely accepted and used all over the world. Millions of users and tens of thousands of merchants have accepted the payment of bitcoin as a digital currency, and the exchange value of bitcoin as a currency is growing. Even e to the consensus that the total amount is fixed and the long-term value is bullish, bitcoin has become a hedge asset similar to gold, and the price has skyrocketed

3.

1. Application of blockchain technology in the banking instry the biggest feature of blockchain technology is decentralization, which will rece a lot of costs for the banking instry. The development of digital currency will make it possible for banks to realize real-time digital transactions. For example, in bill transaction, bank bill transaction always relies on the third party to realize the transfer of valuable documents. Even in electronic bill transaction,

also needs to be authenticated through the information of central bank ECDs system. The blockchain technology can realize the point-to-point value transmission, which no longer needs centralized system control. This not only speeds up the bill transmission speed, but also reces the mistakes caused by human factors. The rection of process will naturally rece the demand of the bank for personnel and save the labor cost of the bank

2, the application of blockchain technology in the insurance instry

blockchain technology also has incomparable advantages in the insurance instry. From the perspective of data management, the application of blockchain technology can effectively improve the risk management and control ability of insurance companies, including the risk supervision of insurance companies and the risk management of policyholders

the application of blockchain technology in the insurance instry can strengthen the internal risk supervision of insurance companies. Blockchain technology can record the daily operation process of insurance company on the node, realize the in-process control of the company's capital flow, investment situation, compensation amount and other business, and improve the company's risk management and control ability

3. Application of blockchain technology in the securities instry

4, blockchain technology and financial infrastructure

blockchain technology is a decentralized mechanism for value exchange, which will lead to earth shaking changes in the existing financial infrastructure characterized by centralization

5. Application of blockchain technology in supply chain, It has become an effective guarantee for enterprise bank's loan credit, financing credit and transaction credit

4. Give you an easy to understand example, you can quickly understand what blockchain is:
in a village, a spent 3000 yuan to buy a cow of B, how to record this account
so a and B found a mutual trusted C to record the account, but later a and C colluded and did not admit that a had bought B's cattle, so the deal became rough and disputes continued
later, B had another cow. Of course, B didn't sell it to a this time, because a had no credit, so he gave it to d. This time, instead of looking for witnesses, they went to the whole village to roar after the transaction. B said Wang Erhua paid 3000 yuan to buy a cow from me, d also went to the whole village to shout that I paid 3000 yuan to buy a cow from B, so there were many people in the village to record the transaction. In this way, there will be no bad debts, which is called decentralized and distributed accounting
here comes the problem
when you yell, are the villagers willing to charge for you, just because you have a big face
therefore, the first person to record accurately will get some bitcoin rewards
someone asked, what if two people finish the first record at the same time
in order to avoid this problem, it is necessary to set rules, for example, to answer a question first, or to record with feet, and it must be written in block letters. If you set a series of rules, there will not be many firsts
in the network, there are a lot of transactions going on every day, and there are also many people recording, and finally they get the reward of bitcoin. This process is the legendary mining
Mining requires a lot of equipment. We call these computer equipment mining machines
in this way, all the processes are in one system. The system will encapsulate the data every 10 minutes to form a box full of data, which we call blocks
with the continuous generation of blocks, they are linked together to form a blockchain.

5. EM is a relative measure

EM is a measure based on typesetting conversion, which defines 1em as the height of capital letters of reference font. For consistency with other metrics, CSS defines 1em as the height of the character box. The size in EM is a decimal or multiple of the reference font size. Therefore, 2em and 200% are the same, and. 75em and 75% represent the same size

you write 2em, which is 200%. Of course, you can't see the effect. If you use 0.2em, you can see the effect.

6. Blockchain technology involves a wide range of disciplines and contents, including network communication, data storage, data encryption, consensus mechanism, security mechanism, cryptography and other related contents. Only by comprehensively mastering these knowledge can we better master the blockchain technology. In addition, the most important thing for learning blockchain technology is to use blockchain in practice, and the real purpose of learning technology is to develop applications that are helpful to life and proction. Xuanling technology has been committed to the development of blockchain technology related applications, and has an experienced development team. If you have relevant intention, you can contact the official website.

7. There are many basic definitions of blockchain. Here, I will analyze the opinions of different schools, and use a more understandable explanation:
blockchain English Name: blockchain, also known as block chain, is a kind of chain data structure that combines data blocks in chronological order, It is a distributed account book that can not be tampered with and forged by means of cryptography
blockchain is essentially a distributed database, which is a series of data blocks generated by using cryptographic methods. Each data block contains the information of a network transaction, which is used to verify the validity of its information (anti-counterfeiting) and generate the next block
2. Working principle
the core potential of blockchain lies in the characteristics of distributed database and how to help transparency, security and efficiency
in the past, institutions used a central database to support transaction processes and calculations. The control of the database is in the hands of its owner, who manages the access and update rights to the database, which limits the transparency and scalability, and makes it difficult for outsiders to ensure that the data records are not manipulated
at the same time, e to technical limitations, distributed database is basically impossible to achieve. But with the development of software, communication and encryption technology, it is possible to build a distributed database across organizations. Blockchain has graally emerged
3. Core idea
the basic idea of blockchain is to establish a network-based public ledger (data block), each block contains the information of a network transaction. All the participating users in the network work together to keep accounts and check accounts. All the data are open and transparent, and can be used to verify the effectiveness of the information. In this way, the authenticity and non tamperability of information can be guaranteed at the technical level without the central server as the trust intermediary.