A local edit history of a file is maintained when you create or modify a file. Each time you edit and save the file, a copy is saved so that you can replace the current file with a previous edit or even restore a deleted file. You can also compare the contents of all the local edits. Each edit in the local history is uniquely represented by the date and time the file was saved.
Only files have local history; projects and folders do not.
Comparing resources with local history
Replacing a resource with local history
Restoring deleted resources from local history
Setting local history preferences
Creating a version of a project