New bitcoins are created through Bitcoin mining. In some sense, Bitcoin mining is similar to digging for gold: It takes time and effort—hence the term mining. The difference between mining gold and mining bitcoins is that a Bitcoin miner uses electricity and computational labor rather than physical labor. Mining is also the process by which new Bitcoin transactions are added to the block-chain, or the public ledger. By adding a new block of transactions to the blockchain, the miner who added the block is rewarded with newly minted bitcoins (as well as old bitcoins in the form of transaction fees).
The number of new bitcoins being mined from each block is diminishing slowly over time and will continue to do so until all 21 million ...