The History view provides a set of actions you can use to get even more information about the project history and make changes to your working copy related with older revisions.
Open - opens the selected revision of the file into the Editor. This is enabled only for files.
Save revision as - saves the selected revision to a file so you have an older version of that file. This option is only available when you access the history of a file, and it saves a version of that one file only.
Compare with working copy - compares the selected revision with your working copy file. It is enabled only when you select a file.
Update to revision - updates your working copy resource to the selected revision. Useful if you want to have your working copy reflect a time in the past. It is best to update a whole directory in your working copy, not just one file, otherwise your working copy will be inconsistent and you will be unable to commit your changes.
Check out from revision - gets the content of the selected revision for the resource into local file system.
Revert changes from this revision - reverts changes which were made in the selected revision. The changes are reverted in your working copy so this operation does not affect the repository file! The action will undo the changes made only in selected revision. It does not replace your working copy file with the entire file at the earlier revision. This is useful for undoing an earlier change when other unrelated changes have been made since the date of the revision. This option is enabled when the resource history was launched for a local working copy resource.
Get Contents - replace the current content of the local version of the selected file with the content of the selected revision.