Cooperation in a shared Workspace may mean that Documents are edited by several authors and revised repeatedly. If the authors used standard Documents, they would have to take care of a lot of administrative chores to manage the succession of Documents and to maintain a history of the changes from one Document to the next. As a safer and more comfortable alternative, the authors might put their BSCW Documents under version control.
The contents of a Document under version control are not simply overwritten, but each time modifications are made, a new version is created as the current version.
The earlier versions are preserved; their sequence identified by version numbers (e.g. 0.1, 0.2, 0.3 etc.). You may access them via the Document's Info page (see section 4.6.2) or directly via a URL with a version number (see section 4.8.5).