Transaction data are data describing an event (the change as a result of a transaction) and is usually described with verbs. Transaction data always has a time dimension, a numerical value and refers to one or more objects (i.e. the reference data).
Typical transactions are:
Typical transaction processing systems (systems generating transactions) are SAP and Oracle Financials.
Recording and retaining transactions is called records management. The record of the transaction is stored in a place where the can be guaranteed and where data are archived/removed following a retention period. The format of the transaction can be data (to be stored in a database), but it can also be a document.
Transaction data can be summarised in a data warehouse, which helps accessibility and analysis of the data.