Revision Control Software is essential on multi-person projects, but it can be useful for solo users as well. The problem is, constantly remembering to use one can make doing so a chore. The free FileHamster versioning software is easy to use and fairly transparent, making it useful for the lone content developer, whether programmer, writer, Web designer, or artist.
Revision control software (or RCS) tracks multiple copies of a file. In addition to the version you're actively using, there are multiple copies stored elsewhere, each one representing an earlier 'saved' copy. On some systems, you must 'check in' and 'check out' versions. This allows you to easily revert to an older version, or document changes which have occurred, or track progress in different ways.
FileHamster will automatically make copies of a file or a directory tree. It monitors when you save changes to a file, and makes a copy of your newest version in its own directory, along with your prior copies. It gives you a chance to add comments when you save, such as "Wrote Body Of Review" or "Updated Print Function". You then keep working as you always have. If you need to switch to an older version, you just go to FileHamster and open an older copy of the file.
FileHamster allows you a good deal of flexibility. You can limit the files it tracks--to just .cpp files, for example, or just .doc files. You can (and should!) limit the number of revisions it tracks--10 is a good number. You can keep it from storing revisions of very large files, such as video clips.
However, many of the things people do with RCS--such as "diff" checks on files--are not included in the free version. This is not so bad, because what you get for free is still useful, but FileHamster has one very annoying quirk--it contains all the menu commands, options, and so forth for FileHamster+, its commercial cousin, and merrily informs you as you pick each one that "You can't do that". Having a free "lite" version is fine, but constantly stumbling over ads for the upgrade when you're simply exploring the interface is very tiresome.
I still recommend FileHamster, though. It's a fine RCS with most of the features a single user needs. Those who need more should look to FileHamster+.