A TXID (Transaction ID) is a unique attribute added to transactions for easy retrieval on the blockchain.

In a transaction on the blockchain, several pieces of information are often public. The address of the sender and the receiver, these are the public keys. These keys are public and unique. The amount is often also public but not unique, multiple people can transfer the same amount. The date and time are also often public. Blockchains can be viewed by anyone. For example, it is possible to look up a public key that shows all transactions and the balance of the wallet. A specific transaction is identified by a TXID (Transaction ID). This unique attribute is created when the transaction is sent. The sender can use this attribute to track the transaction. The attribute is public and thus can also be used by the receiver or third parties to track a transaction. For example, if a transaction does not arrive, the TXID can be used to see if the transaction has already been processed.