What is Bitcoin confirmation?

2019-03-10 00:00:00:

Usually, when receiving Bitcoin, the new owner cannot immediately dispose of them. Once a transaction is completed, it is sent to the Bitcoin network for execution and must be included in a block to become legitimate. The process of including a transaction in the found block is called transaction confirmation. Inclusion in 1 block = 1 confirmation, when such confirmations are typed 6 and higher, the transaction is considered confirmed. This feature was introduced to protect against repeated spending of the same bitcoins.