With regard to cryptocurrency, the number of confirmations is the number of blocks that have been created after a transaction was added to a blockchain. The more confirmations a transaction has, the more secure the transaction is.
Generally, Bitcoin transactions are considered safe after at least six confirmations. This means that five more blocks have been confirmed after the block containing the transaction. Once a transaction is in a block it takes about an hour to receive five more Bitcoin confirmations. Most wallets require a minimum of three such confirmations to save your time.
Actually, the time for processing crypto transactions depends on the miners and the size of transaction fee. In order to confirm a transaction, miners need to use the processing power of a computer or other device to solve an encrypted signature. The more processing power is available, the better the chance the miner can verify the transaction faster. Besides, the miner will try to process transactions that have the highest commission.