Item: An Item can be understood as a "package" containing all relevant data for the part.

Item-Revision: The item contains different development steps of a part, so-called revisions. The item revision is a subgroup of the item; multiple revisions are possible.

Revisions have their name attached to the item ID (A, B, C, D,...) (e.g. 000514/A).

Dataset: Within each item revision there are so-called datasets.

A dataset mostly contains several data (CAD part, preview, attribute forms ...) That means, dataset is a container for files (Iman files).