Learn about bitcoin in nine minutes

3.

The earliest is a kind of network virtual currency. It is characterized by decentralization, anonymity, and can only be used in the digital world. It does not belong to any country or financial institution, and is not subject to geographical restrictions. It can be exchanged anywhere in the world. Therefore, it is used as a money laundering tool by some criminals. In 2013, the U.S. government recognized the legal status of bitcoin, making the price of bitcoin soar

< H2 > extended information:

bitcoin is e-cash similar to e-mail. Both parties need "bitcoin wallet" similar to e-mail and "bitcoin address" similar to e-mail address. Just like sending and receiving e-mail, the remitter pays bitcoin directly to the other party through a computer or smart phone according to the recipient's address

starting from the essence of bitcoin, the essence of bitcoin is actually a special solution generated by a bunch of complex algorithms. A special solution is one of the infinite (in fact, bitcoin is finite) solutions that can be obtained from the equations. Every particular solution can solve the equation and is unique

many websites for technology players have begun to accept bitcoin transactions. Websites such as mtgox and btcchina, as well as some Taobao stores, can even accept services such as bitcoin exchange for us dollars and euro. There is no doubt that bitcoin has become a real currency in circulation, rather than a virtual currency like Tencent Q coin

4. Bitcoin is a virtual cryptocurrency based on decentralization, peer-to-peer network, consensus initiative, open source, and blockchain as the underlying technology. It was proposed by Nakamoto in 2008 and born in 2009. Bitcoin does not have a centralized issuer, which is generated by the calculation of network nodes. It can be bought and sold on any computer connected to the Internet, and it has a strong scarcity

starting from the essence of bitcoin, the essence of bitcoin is actually a special solution generated by a bunch of complex algorithms. A special solution is one of the finite solutions of a system of equations. Every particular solution can solve the equation and is unique. In the metaphor of banknotes, bitcoin is the number of the top word of a banknote. If you know the number of the top word on a banknote, you have the banknote. The process of mining is to constantly seek the special solution of the equation system through huge amount of calculation. The equation system is designed to have only 21 million special solutions, so the upper limit of bitcoin is 21 million

to mine bitcoin, you can download the special bitcoin computing tools, register various cooperation websites, fill the registered user name and password into the computing program, and then click the operation to officially start. After completing the installation of bitcoin client, you can directly obtain a bitcoin address. When others pay, you only need to paste the address to others, and you can pay through the same client. After installing the bitcoin client, it will assign a private key and a public key. You need to back up the wallet data containing your private key to ensure that your property is not lost. Unfortunately, if the hard disk is completely formatted, personal bitcoin will be completely lost<

currency features
Decentralization: bitcoin is the first distributed virtual currency, and the whole network is composed of users without a central bank. Decentralization is the guarantee of bitcoin's security and freedom

Global Circulation: bitcoin can be managed on any computer connected to the Internet. No matter where you are, anyone can dig, buy, sell or collect bitcoin

exclusive ownership: private key is required to manipulate bitcoin, which can be stored in any storage medium in isolation. No one can get it except the user himself

low transaction cost: bitcoin can be remitted free of charge, but a transaction fee of about 1 bitfen will be charged for each transaction to ensure faster transaction execution

no hidden cost: as a means of payment from a to B, bitcoin has no cumbersome quota and proceres. If you know the other party's bitcoin address, you can pay

cross platform Mining: users can explore the computing power of different hardware on many platforms

advantages
completely decentralized, without issuing institutions, it is impossible to manipulate the number of issues. Its distribution and circulation are realized through open-source P2P algorithm

anonymity, tax exemption and supervision free

robustness. Bitcoin is completely dependent on P2P network and has no distribution center, so it cannot be shut down externally. Bitcoin price may fluctuate and collapse, and many governments may declare it illegal, but bitcoin and its huge P2P network will not disappear

cross border. Cross border remittance will go through layers of exchange control agencies, and the transaction records will be recorded by many parties. But if you trade with bitcoin, enter the digital address directly, click the mouse and wait for the P2P network to confirm the transaction, a lot of money will pass. It does not go through any regulatory agencies and will not leave any cross-border transaction records

it is difficult for the cat to survive. Because bitcoin algorithm is completely open source, anyone can download the source code, modify some parameters, recompile, and create a new P2P currency. But these counterfeit currencies are fragile and vulnerable to 51% attacks. Any indivial or organization, as long as it controls 51% of the computing power of a P2P currency network, can manipulate transactions and currency value at will, which will be a devastating blow to P2P currency. Many Shanzhai coins die in this link. The bitcoin network is robust enough. If you want to control 51% of the computing power of the bitcoin network, the number of CPUs / GPUs required will be astronomical

disadvantages
the vulnerability of trading platform. The bitcoin network is robust, but the bitcoin trading platform is fragile. Trading platform is usually a website, which will be attacked by hackers or shut down by competent authorities

transaction confirmation takes a long time. When bitcoin wallet is first installed, it will consume a lot of time to download historical transaction data blocks. While bitcoin transaction, in order to confirm the accuracy of data, it will take some time to interact with P2P network, and the transaction will be completed only after the whole network is confirmed

the price fluctuates greatly. Due to the intervention of a large number of speculators, the price of bitcoin for cash fluctuates like a roller coaster. Making bitcoin more suitable for speculation rather than anonymous trading

the public did not understand the principle, and the traditional financial practitioners resisted. Active netizens understand the principle of P2P network and know that bitcoin has no legal person to manipulate and control. But the public doesn't understand, and many people can't even tell the difference between bitcoin and q-coin“ "No issuer" is the advantage of bitcoin, but in the view of traditional financial practitioners, "no issuer" currency is worthless.

5. Throughout history, there have been cases of gold, goods and even land confiscation in times of crisis. It is also disturbing that, as we have seen in Venezuela, people there are struggling with high inflation. Sometimes it is extremely difficult to convert money into another currency, which makes people feel helpless and can only watch their life savings be worthless. Bitcoin is very different. It is in electronic form and has no boundary restrictions. It can be transferred without any intermediary. Anyone who connects to a mobile device or the Internet can use it. All transactions are permanently recorded in the public ledger, and there is no dispute about ownership
in a recent article in the New York Times, a Venezuelan economist described how bitcoin became a part of Venezuela's daily life, so that on a mainstream bitcoin trading platform, Venezuela's trading volume ranked second only to Russia in the world. But bitcoin is not just used to protect wealth in extreme conditions. In general, bitcoin is also an excellent choice for portfolio diversification, and it should be seen as part of a comprehensive wealth preservation strategy.

6. Go to bitcoin news network to see more bitcoin news, as well as market and technology
the birth of bitcoin
the birth of bitcoin should be on November 1, 2008. A man with the pseudonym of "Nakamoto Tsung" published a paper on the Internet. In this paper, he described in detail a new monetary system, which he named "bitcoin"

then, on January 3 of the next year, the first bitcoin program was born in the hands of Nakamoto Tsung, along with the first 50 bitcoins from mining. After that, he began to fade out until he disappeared completely

so far, people have not found out the real identity of this person, even if today's operators, Internet giants and the government have firmly grasped people's behavior on the Internet

he often switches between American and British English when he speaks. He goes online at different times of the day at random to hide his nationality and time zone; He hides his IP address, encrypts his email, and deliberately forges some writing and speaking styles to confuse the public; Besides, he is also an expert in cryptography. By the way, the place where he published his paper is called & quot; Cryptography mailing list & quot

so bitcoin was born with a hacker spirit: against the censorship imposed by any force

of course, we can also see that if a hacker who invented the anonymous currency system can't be anonymous, the whole thing will become a joke< But fortunately, Nakamoto didn't let us down

1. What is currency
I find that I can't run this section in any case to clarify what is bitcoin. I am not an expert in the field of economics. I can only talk about this issue in a very superficial and intuitive sense However, as far as the theme expressed in the title is concerned, it seems to be enough)

it has been mentioned in senior high school textbooks (remember?), Money is the medium to store value. If a thing wants to become money, it must meet the following requirements:

1) scarcity

that's why gold can be used and sand can't be used as money. Scarcity can be understood as the difficulty of obtaining it. The more scarce it is, the more difficult it is to obtain it. An intuitive understanding is as follows: assuming that your monthly salary is 5000 yuan, it means that the scarcity of RMB is just such a degree, that is, you have to pay a month's labor to get 5000 yuan. You won't agree to pay your salary with 5000 grains of sand, because instead of working for a month to get it, you can easily get it by walking around the beach

how does the current financial system guarantee the scarcity of money? Control distribution. The issue of money is firmly in the hands of the central bank, so that the amount of money can be controlled (so you now know that it is illegal to print money without permission). Back to the example just now, you agree to pay you a month's salary with 5000 yuan because the circulation of RMB has just reached this level. If the circulation of RMB doubles and the scarcity decreases, you should ask for 10000 yuan to pay your salary (but the response of the market is often not so fast. During this period, your wealth is actually deprived - your labor should have received 10000 yuan, but only 5000 yuan in return)

2) transactional

of course, the purpose of currency is to trade. As many people tell you, money is spent, not brought into the coffin. So in addition to meeting scarcity, the more convenient it is for a thing to trade, the more it meets the standard of ideal currency. Therefore, in the history of currency, silver dollar has replaced shells, paper money has replaced silver dollar, and digital currency is graally replacing paper money

the "transaction" here refers to the transfer of property from one party to the other, that is, the decrease of one party's property and the corresponding increase of the other party. For physical currency, it happens very naturally. A wants to give 100 yuan to B. when the 100 yuan note is transferred from a's hand to B's hand, the transaction is completed. A's property is reced by 100 yuan and B's property is increased by 100 yuan. There is no third party involved in this process, which is completely a private act between a and B; However, when the transaction takes place at the level of digital currency, it is not so simple. Party A has to give 100 yuan to Party B. how can we ensure that the transaction is completed? Suppose that a and B record their wealth on their respective computers, how can we ensure that when B adds 100 yuan to them, a actually subtracts 100 yuan from them? Now we have to bring in a third party - the guy we call the bank. When a wants to transfer 100 yuan to B, he doesn't directly give it to B, but to the bank, "please transfer my 100 yuan to B", so the bank dected 100 yuan from a's account and added 100 yuan to B's account Let's assume that it generously does not charge any transaction fee)

the above is a rough model of modern monetary system. The biggest disadvantage of this model is that people have to trust a central system

the transaction of digital currency must rely on the bank, and a person's bank account number may be censored, restricted or even deprived. When one party wants to transfer his wealth to the other party, the bank can charge a high fee or refuse directly (for example, you try to remit a sum of money to a relative in the United States)

the issuance of money must rely on the central bank. Well, it's a well-known secret: the currency has been devaluing, or over issuing (think of the $100 20 years ago and the $100 now). I quote two paragraphs, one of which is Keynes's saying, "through a continuous process of inflation, the government can confiscate a part of citizens' wealth secretly and unknowingly. In this way, we can deprive the people of their wealth at will, while making the majority poor, we can make the minority rich, Another paragraph, from Hayek, "the government can not restrain the impulse to issue money indiscriminately."

is it possible to design a monetary system in which we do not need a central institution and are not forced to trust any third party, so as to make the issuance of currency transparent and controllable, and the transaction of currency private and secure

guess what

2. What is bitcoin
so we can now answer that bitcoin is an e-money system with decentralized distribution and transaction. In this system, the circulation of money is transparent and predictable, and the transaction of money uses the cooperation of the whole network to ensure the security of the transaction

next, I will graally dismantle the principle of bitcoin. It should be noted that bitcoin, as a proct already in use, has a lot of details. The purpose of this article is to explain the basic principles of bitcoin to readers without technical background, so these details will not be covered. For example, the address of the wallet is not the public key, but the second hash value of the public key; The difficulty requirement of blockchain is not to hash all the contents of blockchain once; wait. But for the sake of brevity, without affecting the explanation of the basic principles, these are simplified. I hope you can understand them

2.0. Bitcoin network is composed of many nodes running bitcoin programs
bitcoin is a network composed of many equal nodes

a node is a bitcoin program. Any machine that can connect to the Internet and have certain computing power can run this program - so your home computer can also be used as a node in the bitcoin network:)

nodes can communicate with each other. At the same time, bitcoin has a set of mechanism that allows a node to send messages to all other nodes, This behavior is called "broadcasting."

2.1. Blockchain - a public account book
let's go back to the example of banks. The most basic function of a bank is to maintain an account book, which only needs to record every transaction truthfully. For example, Wang Xiaoming transferred 30 yuan to Zhang Damao on X, year X; On y, y, y, y, Zhang Da Mao transferred 12 yuan to Li Xiao Dou, and so on. According to this account book, we can find all the transaction records of a person, so we can calculate the current account balance of the person. For example, since Li Xiaodou started to build a bank account, the total amount of transactions transferred in is 500 yuan, and the total amount of transactions transferred out is 300 yuan. Then it can be calculated that the balance of Li Xiaodou's account must be 200 yuan at this time

maintain this account book, and as the only maintainer (only the bank has the right to view and modify), the bank's responsibility as a trading center is completed

bitcoin also has an account book, but unlike banks, this account book is open and anyone can view and review it

this account book is called & quot; Blockchain & quot;. You can think of blockchain as a pamphlet. Every page of the pamphlet is full of transaction information, and new pages are constantly added<

2.2 Wallet - an account composed of a pair of public keys and private keys
the above section explains what a bitcoin account book is. This section will explain the ownership of funds in this account book, that is, the account system of bitcoin

there are essential differences between accounts in bitcoin and bank accounts

under a bank account, the bank records the identity information of the owner of the account (think back to the information you submitted when you went to the bank to open an account: photo, ID card, telephone number, home address...), so as long as you can prove your identity to the bank, you will get the ownership of the property under your name. In this model, the bank plays the role of an omniscient God: he knows the wealth information of real people. We have no choice but to pray to God not to let our information out or use it for evil

in the world of bitcoin, there is no such institution as bank, which will not force people to reveal their identities in exchange for the security of funds. Bitcoin's account is simply composed of two strings of numbers, which are called "public key" and "private key" respectively, and there is nothing else

the mathematical characteristics of these two numbers - a data encrypted by a private key can only be decrypted by a public key, so-called asymmetric encryption - enable them to perfectly implement the functions required by an account (called a wallet in the bitcoin world)

we take the public key as the account address - also known as the wallet address in the bitcoin world - which is similar to the account number in the banking system, that is, when you tell someone "please call 300 yuan for my account number", you need to tell them. For the bank, it is "China Merchants Bank 6214850200251100", compared with the special currency, it is "

the private key is the * only * certificate to prove the ownership of the wallet. You can hold it by proving that you are the private key of the wallet

7. The premise of foreign exchange is real foreign exchange. Foreign exchange is used to hedge against international currency and push your money to the international market. Digital currency is private disk, gambling

8. If you download apps, you can download them directly from the app market, but some apps that have not been put on the shelves can be downloaded directly from the browser.

9. Bitcoin is a kind of universal encrypted electronic currency in the world, and it is completely autonomous by users. The concept of bitcoin was first proposed by Nakamoto in 2009. Unlike most currencies, bitcoin does not rely on specific currency institutions to issue. It is generated by a large number of calculations based on specific algorithms. Bitcoin economy uses a distributed database composed of many nodes in the whole P2P network to confirm and record all transactions, and uses cryptography design to ensure the security of all aspects of money circulation