Yesterday we got a question from a customer whether is was possible to have versioning on a library, and at the same time disabling the check in/ check out option. I didn't know, but after a view minutes of looking around, my colleague Casper found the settings in the document library settings under Versioning Settings.
You can actually configure a couple of interesting settings on this page.
Require content approval for submitted items? This is a setting you will especially use on development environments to prevent having to approve every change in for instance a master page or a page layout.
Create a version each...