An Unconfirmed Transaction refers to a blockchain transaction, such as buying, selling, or transferring a cryptocurrency, that hasn’t been permanently recorded to the blockchain.
An unconfirmed transaction status means that the network of miners or validators hasn’t completely examined the transaction in full, to determine that there aren’t any pending transactions involving the same cryptocurrency being used.
In the event that a cryptocurrency sender removes or reduces transaction fees or doesn’t increase fees on a congested network, miners and validators may simply ignore the transaction.
Once a transaction has remained unconfirmed for a long time, the transaction is not added to a block, and the network may simply drop it completely.