h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Not to be pedantic but a skin, in FPS terms, is not a 3D model. It's the texture that covers a model or models (in this case a man shaped set of models) hence the term "skin". In CS as with most FPS, you can change your skin and give the model a completely different look without actually changing the shape of the model. This is how there's only one model set (afaik) for the player(s) in CS just with lots of different textures, so you can look like a terrorist in snow camo or with a jacket and glasses, or a special forces soldier or whatever.