Bitcoin is a decentralized cryptocurrency

Beschreibung

Bitcoin (BTC) ist die bekannteste Kryptowährung.
Die digitale Währung wurde im Januar 2009 nach dem Zusammenbruch des Immobilienmarktes geschaffen.
Sie folgt den Ideen, die der geheimnisvolle und pseudonyme Satoshi Nakamoto in einem Weißbuch dargelegt hat.
Bitcoin is administered through a decentralized peer-to-peer network
Bitcoins are issued according to rules agreed to by the majority of the computing power within the Bitcoin network. The core rules describing the predictable issuance of bitcoins to its verifying servers, a voluntary and competitive transaction fee system and the hard limit of no more than BTC 21 million issued in total.

Einheiten

Einheit	Entpricht
1 BTC	1.000 mBTC
1 mBTC	1.000 bits
1 bit	100 satoshi
1 BTC	100.000.000 satoshi

Blockchain

Transactions

Transactions are verified by network nodes through cryptography and recorded in a public distributed ledger called a blockchain.
All transactions are visible on the block chain and can be viewed using a hex editor. The Blockchain Browser is a site where every transaction included in the Blockchain can be viewed in a human-readable way. This is useful for viewing the technical details of transactions in action and for verifying payments.

Mining

Mining is the process of adding transaction records to Bitcoin's public ledger of past transactions (and a "mining rig" is a colloquial metaphor for a single computer system that performs the necessary computations for "mining". This ledger of past transactions is called the block chain as it is a chain of blocks. The blockchain serves to confirm transactions to the rest of the network as having taken place. Bitcoin nodes use the blockchain to distinguish legitimate Bitcoin transactions from attempts to re-spend coins that have already been spent elsewhere.

Mining has two goals:

Set the transaction history in such a way that it is computationally impossible to change it by any single entity.
Introduction of bitcoins into the system: miners are paid any transaction fees, as well as a reward for the created coins.

Difficulty

Mining a block is difficult because the SHA-256 hash of a block's header must be lower than or equal to the target in order for the block to be accepted by the network. This problem can be simplified for explanation purposes: The hash of a block must start with a certain number of zeros. The probability of calculating a hash that starts with many zeros is very low, therefore many attempts must be made. In order to generate a new hash each round, a nonce is incremented.