So today I would like to go over the importance of version control.
Take for example I was working on a program, I made some changes and it was working. Now rather then checking in my file and version controlling it, I just started modifying it. About half ways through I realized I meant to re-save the file somewhere but instead overwrote the changes that I had originally working.
When you've gotten a particular program working at some point, if you're dedicated enough to stick to version control, you check it in, then keep working, now if you have made changes and wish to revert to a previous working state it's REALLY EASY. Now of course simple enough you can just save multiple copies of a file, and keep renaming it and everything else. If you use version control you really only "see" one file and you just keep checking it in.
I have SVN setup on my server, and am using Tortoise SVN for my window's machine, and am enthralled with it. When you do a checkout in SVN it ends up copying the checked out folder into your current directory. Now when you make changes it shows a different icon on the folders so you can visually see that it's needing to be committed. Now if you're working with multiple machines/people you will want to make sure you update before commiting.
Once you've committed changes you're set.
Good luck and let me know if you need any help setting up your very own SVN server.