Like paper money and gold before it, bitcoin and ether allow parties setgenerate bitcoin chart exchange value. Unlike their predecessors, they are digital and decentralized.
For the first time in history, people can exchange value without intermediaries which translates to greater control of funds and lower fees. Количество транзакций биткойнов за последние 24 часа. Average block generation time of 2016 blocks. Block generation time is also known as confirmation time.
Average block generation time of 1008 blocks. It won’t do anything bad to your computer, we promise. Your computer—in collaboration with those of everyone else reading this post who clicked the button above—is racing thousands of others to unlock and claim the next batch. For as long as that counter above keeps climbing, your computer will keep running a bitcoin mining script and trying to get a piece of the action. So what is that script doing, exactly? Let’s start with what it’s not doing.
Your computer is not blasting through the cavernous depths of the internet in search of digital ore that can be fashioned into bitcoin bullion. There is no ore, and bitcoin mining doesn’t involve extracting or smelting anything. It’s called mining only because the people who do it are the ones who get new bitcoins, and because bitcoin is a finite resource liberated in small amounts over time, like gold, or anything else that is mined. What bitcoin miners actually do could be better described as competitive bookkeeping. Miners build and maintain a gigantic public ledger containing a record of every bitcoin transaction in history. Every time somebody wants to send bitcoins to somebody else, the transfer has to be validated by miners: They check the ledger to make sure the sender isn’t transferring money she doesn’t have.
If the transfer checks out, miners add it to the ledger. And for this service, they are rewarded in bitcoins. Or rather, some miners are rewarded. Miners are all competing with each other to be first to approve a new batch of transactions and finish the computational work required to seal those transactions in the ledger. With each fresh batch, winner takes all. It’s the computational work that really takes time, and that’s mostly what your computer is doing right now.
It’s trying to solve a kind of cryptographic problem that involves guessing and checking billions of times until it finds an answer. If this all seems pretty heady, that’s because mining is an elaborate solution to a tough problem that plagues every currency—double spending. Double spending and a public ledger As the name implies, double spending is when somebody spends money more than once. It’s a risk with any currency. But bitcoin is completely digital, and it has no third parties.
The idea of an overseeing body runs completely counter to its ethos. So if you tell me you have 25 bitcoins, how do I know you’re telling the truth? The solution is that public ledger with records of all transactions, known as the block chain. We’ll get to why it’s called that shortly. If all of your bitcoins can be traced back to when they were created, you can’t get away with lying about how many you have. So every time somebody transfers bitcoins to somebody else, miners consult the ledger to make sure the sender isn’t double-spending. If she indeed has the right to send that money, the transfer gets approved and entered into the ledger.
Using a public ledger comes with some problems. How can you make every bitcoin exchange completely transparent while keeping all bitcoin users completely anonymous? If the ledger is totally public, how do you prevent people from fudging it for their own gain? There is no such thing as a bitcoin account Bitcoin’s ledger deals with the privacy issue through a bit of accounting trickery. The ledger only keeps track of bitcoin transfers, not account balances.
In a very real sense, there is no such thing as a bitcoin account. Here’s how it works: Say Alice wants to transfer one bitcoin to Bob. First Bob sets up a digital address for Alice to send the money to, along with a key allowing him to access the money once it’s there. When Alice clicks a button to send the money to Bob, the transfer is encoded in a chunk of text that includes the amount and Bob’s address.
That transaction record is sent to every bitcoin miner—i. Now, say Bob wants to pay Carol one bitcoin. Carol of course sets up an address and a key. Bob hasn’t already transferred that bitcoin to somebody else. After validating the transfer, each miner will then send a message to all of the other miners, giving her blessing. If Bob’s transfer to Carol passes muster, then it, too, will be added to the ledger.
The ledger tracks the coins, but it does not track people, at least not explicitly. Assuming Bob creates a new address and key for each transaction, the ledger won’t be able to reveal who he is, or which addresses are his, or how many bitcoins he has in all. It’s just a record of money moving between anonymous hands. There is no master document Now for the trickier problem: keeping the ledger secure. The first thing that bitcoin does to secure the ledger is decentralize it.