Bitcoin[a] (₿) is adigital and globalmoney systemcryptocurrency. It allows people to send or receive cryptocurrency units across theinternet, even to someone they don't know or don't trust. It is the first of its kind technology that allows thetransfer of digitalscarcity across the internet without needing a third party. Cryptocurrency units can be exchanged without being linked to a real identity. Themathematical field ofcryptography is the basis for Bitcoin'ssecurity.
Bitcoin was invented by someone using the nameSatoshi Nakamoto.[14] A Bitcoin address, or simply address, is an identifier of 26-35 letters and numbers, beginning with the number 1, 3, or bc1, that represents a possible destination for a bitcoin payment. Addresses can be generated at no cost by any user of Bitcoin. For example, using BitcoinCore, one can click "New Address" and be assigned an address. It is also possible to get a Bitcoin address using an account at an exchange or online wallet service.
The domain name "bitcoin.org" was registered on 18 August 2008.[15] On 31 October 2008, a link to a paper authored bySatoshi Nakamoto titledBitcoin: APeer-to-Peer Electronic Cash System[3] was posted to a cryptography mailing list (they were the forerunners of social media).[16][17]
One of thedifferences between using bitcoin and using regular money online is that bitcoin can be used without having an internet connection to link any sort of real-world identity to it. Unless someone chooses to link their name to a bitcoin address, it is hard to tell who owns the address. Bitcoin does not keep track of users; it keeps track of addresses where the money is. Each address has two important pieces ofcryptographic information, or keys: a public one and a private one.
The public key, which is what the "bitcoin address" is created from, is similar to an email address; anyone can look it up and send bitcoins to it. The private address, or private key, is similar to an emailpassword; only with it can the owner send bitcoins from it. Because of this, it is very important that this private key is keptsecret. To send bitcoins from an address, you prove to the network that you own the private key that belongs to the address, without revealing the privatekey. This is done with a branch of mathematics known aspublic-key cryptography.
A public key is what determines the ownership of bitcoins, and is very similar to anID number. If someone wanted to send you bitcoins, all you would need to do is supply them your bitcoin address, which is a version of your public key that is easier to read and type. For example, if Bob has 1 bitcoin at the bitcoin address "ABC123," and Alice has no bitcoins at the bitcoin address "DEF456," Bob can send 0.5 bitcoins to "DEF456." As soon as the transaction is processed, Alice and Bob both have 0.5 bitcoins. Anyone using the system can see how much money "ABC123" has and how much money "DEF456" has, but they cannot tell anything about who owns the address.
A Bitcoin private key has 52 characters consisting of letters and numbers. It is, simply, a random number. The set of numbers that can make up a private key is extremely large. The Bitcoin private key can be any number from a maximum of 2 to the power of 256.[20]
In the example above, "ABC123" and "DEF456" are the bitcoin addresses of Bob and Alice. But Bob and Alice each have a second key which only they individually know. This is the private key, and it is the "other half" of a Bitcoin address. The private key is never shared, and allows the owner of the bitcoins to control them. However, if the private key is not kept secret, then anyone who sees it can also control and take the bitcoins there. This happened on live TV whenBloomberg's Matt Miller accidentally showed a private key to viewers.[21] The money was taken immediately. The person who took it, told others about it later, saying "I'll send it back once Matt gives me a new address, since someone else can sweep [empty] out the old one."
Sites or users using the Bitcoin system are required to use a globaldatabase calledblockchain. Blockchain is a record of all transactions that have taken place in the Bitcoin network. It also keeps track of new bitcoins as they are generated. With these two facts, the blockchain can keep track of who has how much money at all times.[source?]
The process of generating the bitcoins is called mining.[20] To generate a bitcoin, a miner must solve a math problem. However, the difficulty of the math problem depends on how many people are mining for bitcoin at the moment. Because of how complicated the math problems usually are, they must be calculated with very powerfulprocessors. These processors can be found in CPUs, graphics cards, or specialized machines called ASICs. People who use these machines to mine bitcoins are called miners. Miners either compete with one another or work together in groups to solve a mathematical puzzle. The first miner or group of miners to solve the particular puzzle are rewarded with new bitcoins.
The puzzle is determined by the transactions being sent at the time and the previous puzzle solution. This means the solution to one puzzle is always different from the puzzles before. Attempting to change an earlier transaction, maybe to fake bitcoins being sent or change the number of someone's bitcoins, requires solving that puzzle again, which takes a lot of work, and also requires solving each of the following puzzles, which takes even more work. This means a bitcoin cheater needs to outpace all the other bitcoin miners to change the bitcoin history. This makes the bitcoin blockchain very safe to use.
When miners mine a block of bitcoin, they receive a reward. This reward gets cut in half every 210,000 blocks, which occurs roughly once every 4 years.[22] During Bitcoin's inception, the block reward was 50 BTC. It was halved to 25 BTC on November 28th, 2012, and to 12.5 BTC on July 9th, 2016. As of May 11th, 2020, the block reward has been 6.25 BTC.
A paper printable bitcoin wallet consisting of one bitcoin address for receiving and the corresponding private key for spending.
A popular image associated with Bitcoin is aQR code. QR codes are a group of black and white boxes that are similar to barcodes. Barcodes are a row of lines, and QR codes are a grid of squares. Bitcoin uses QR codes because they can store more information in a small space, and a camera such as asmartphone can read them. The two QR codes on the Bitcoin note are the public and private addresses, and can be scanned with a number of online tools.
Bitcoin is being moved from a web based cryptocurrency exchange to a hardware wallet.
Everyone in the Bitcoin network is considered a peer, and all addresses are created equal. All transactions can take place solely from peer to peer, but a number of sites exist to make these transactions simpler. These sites are called exchanges. Exchanges provide tools for dealing in Bitcoin. Some allow the purchase of Bitcoin from external accounts, and others allow trading with other cryptography-based currencies like Bitcoin. Most exchanges also provide a basic "wallet" service.
Wallets provide a handy way to keep track of all of a user's public and private addresses. Because addresses arepseudo andanonymous, anyone can have as many addresses as they want.[source?] This is useful for dealing with multiple people, but it can get complicated to manage multiple accounts. A wallet holds all of this information in a convenient place, just like a real wallet would. A backup of a wallet prevents 'losing' the bitcoins.
During the2010s, Bitcoin has gained the attention of the mainstream media.[23] Adoption growth has not only happened for consumers,[24] but also for many companies, who are looking to make use of all of the advantages of Bitcoin.
As of 2018, Bitcoin was most popular cryptocurrency, followed byEthereum andLitecoin.[25]
Bitcoin has often been criticized for its unstable price, its network's highelectricity consumption, and for its high transaction fees. Additionally, it has been criticized for having characteristics in common withPonzi,pyramid schemes and abuse formoney laundering. Bitcoin owners regularly complain about losing their password, making their bitcoins permanently inaccessible.[27] Also, people often use Bitcoin to buyillegal things on thedark web because it hides theiridentity, isn't controlled by one group, and is easy to use across countries.
↑Bustillos, Maria (2 April 2013)."The Bitcoin Boom".The New Yorker. Condé Nast.Archived from the original on 27 July 2014. Retrieved22 December 2013.Standards vary, but there seems to be a consensus forming around Bitcoin, capitalized, for the system, the software, and the network it runs on, and bitcoin, lowercase, for the currency itself.
↑Metcalf, Allan (14 April 2014)."The latest style". Lingua Franca blog. The Chronicle of Higher Education (chronicle.com). Archived fromthe original on 16 April 2014. Retrieved19 April 2014.
↑S., L. (2 November 2015)."Who is Satoshi Nakamoto?".The Economist. The Economist Newspaper Limited.Archived from the original on 21 August 2016. Retrieved23 September 2016.
