Bitcoin transactions are verified by a process known as mining. Mining requires powerful computers to solve complex mathematical problems in order to confirm a transaction and add it to the public ledger. This ledger, known as the blockchain, is a record of all Bitcoin transactions that have taken place since the network began.
Mining is essential to the functioning of the Bitcoin network, as it ensures that every transaction is valid and prevents double spending. The mining process is also used to create new Bitcoins, as miners are rewarded with a set amount of the cryptocurrency for each block they successfully mine.