From OpenSCADAWiki
Archiving-history of the TP data
The data obtained early are considered current, that is, those that are periodically updated and characterise the value of the parameter TP for the current time. At the same time, the previously read values are lost when they are overwritten by the current value, that is, their history is missing. In many tasks, the archive-history of the read values of TP parameters is required, for which OpenSCADA provides the subsystem "Archives-History" where we need to create archivers of values and messages, for violations, and specify our parameters for archiving their values there.