In Bitcoin, a block—which groups together transactions—also serves as a unit of mining
A collection of Bitcoin transactions is called a block, and it also serves as the unit of mining through which miners earn Bitcoin as a reward.
Individual transactions, such as transfers made by users to other parties, are not finalized until they are confirmed; inclusion in a block serves as a sign of confirmation.
Since blocks are generated through mining approximately every 10 minutes, if a large number of transactions occur at the same time—or if there was a concentration of transactions prior to that point and no queue of pending confirmations—the transfer can be completed in as little as 10 minutes. If the timing is right between the generation of the previous block and the next, the transfer can be completed in just a few minutes. This explains why many users prefer Bitcoin for international transfers, which can take several days via traditional bank transfers.
Note that transactions are not added to blocks strictly in the order they were made; the order is also influenced by the size of the fee offered to the miner. Therefore, offering a higher fee can be expected to speed up the process of having your transaction added to a block.
A single block does not contain just one user’s transaction; instead, multiple transactions are grouped together within the currently established 1GB data limit and time constraints.
When a new block is added to the blockchain—which serves as a history of all transactions made to date—a coinbase, which serves as a reward for the miner, is generated simultaneously.
