Usually I recommend either GIT or SVN. If you use Windows, SVN may be a better option (I believe the GIT binaries are still in beta for Windows, and the SVN clients are better). I'd also recommend registering for a hosted version system (such as github or beanstalk). Most services offer a free option, and will provide far better data replication than an any individual could create. Lastly, check out a GUI client (such as Tortise SVN) or check for integrations with the IDE you use for editing code.
Last question first: what language you're using doesn't really matter. Even for text documents, Word documents, etc., a source control system will keep track of your versions.
As for which one to use, there are a number of free ones available, that require different levels of administration and expertise. If you're mostly comfortable with Windows programs, SourceGear licenses their Vault product free for single users.
Open source repositories are also not uncommon. Subversion is widely used, but does require a fair amount of server administration expertise.
Go with something like http://beanstalkapp.com
SVN is probably more conceptually easy to understand than Git, and it has more users - hence more tools and easier to find help.
The tutorial at http://hginit.com/ covers a lot of ground regarding the concepts behind version control, specifically distributed version control. Mercurial is the focus of the tutorial, but the concepts extend to git as well, and to other SCMs to a small degree.
My biggest recommendation is just to start using some version control, right now. It'll change the way you work--honestly.
(full disclosure: I work for Fog Creek, the sponsor of the hginit tutorial)
For an individual, Bazaar in Solo mode is very easy to use. Later if you want a multi-user configuration, other "workflows" are possible.
I'd recommend Subversion (SVN) using the Red Bean Subversion book as a guide. Start with Appendix A, then go through chapters 1, 2 at least.
This is my recommendation primarily because it is how I started with version control, not because I think SVN is better than other version control systems.
I agree with Kevin Gessner just start using something and feel the change wash over you!