From Tortoise Team
TortoiseSVN is a really easy to use Revision control / version control / source control software for Windows.
Since it's not an integration for a specific IDE you can use it with whatever development tools you like.
TortoiseSVN is free to use. You don't need to get a loan or pay a full years salary to use it.
Features of TortoiseSVN/Subversion
* Easy to use
- all commands are available directly from the windows explorer.
- only commands that make sense for the selected file/folder are shown. You won't see any commands that you can't use in your situation.
- See the status of your files directly in the Windows explorer
- descriptive dialogs, constantly improved due to user feedback
- allows moving files by right-dragging them in the windows explorer
* All Subversion protocols are supported
* Powerful commit dialog
integrated spell checker for log messages
auto completion of paths and keywords of the modified files
text formatting with special chars
* The big picture
Can create a graph of all revisions/commits. You can then easily see where you created a tag/branch or modified a file/folder
Graphs of commit