The history of a document includes all of the actions that have been performed on that major version like:
History is saved for each document major version separately and can be viewed as described in Viewing prior versions. Each action includes the date and time that the action was performed and the name of the user who performed the action.
To view the history of a document:
In the Document group, click History. A page listing the base properties appears. The history of the item is listed under Document history.
Related concepts
Working with comments and discussions
About transferring properties with Office documents
Related tasks
Viewing and editing document properties
Locking and unlocking documents