[demosthenes2k8]

iblis, that works...adequately...for one person, or maybe even two, but with a larger team || a more complex project, it's not always the way to go. Source Control allows you to track multiple design paths safely (person A is implementing feature X, person B is testing feature Y), as well as have safe, simple backups of your files. Especially if you need to jump back several times to fix a bug.
TL;DR: Use source control. It may seem to be more than needed, but it can save you at competition.