Documents: Saving and Editing

IS there a way to edit a document in the system and have the changes take, without savinging it into the desktop and creating a copy? Or even creating a copy and having the ability to save changes.( had a user work on document in system and no changes were saved

Something like this?
If one user already has a document-in-progress open, system alerts the next user and prevents accidental overwriting between concurrent users.

Document Workflow Tools.
System automatically saves and names multiple versions of the same document, and you can roll back to a previous version if needed.
Plus, easily create and review comments for each online document, and create an audit trail on document histories.

Thank you for your time.
Manya