UV mapping is the coordinates for the textures you might say, without it you'll have a mesh without a texture. Bump mapping is a way to simulate bumps on textures. It requires the texture and a normal map of the texture, a normal map decides where the bumps are and how pronounced they should be. Normal maps can easily be created by programs such as CrazyBump. I use blender and i've learned most of it by watching tutorials on youtube, i just search for blender and whatever i want to learn, like blender uv mapping, blender bezier curves etc..
Thanks for the explanation, Vurt.
Blender was too... difficult for me. I guess I will dig for some more tuts, just wanted to hear your personal look on these things, that is: how you explain it, most of the times, descriptions given by fellow people (modders this case) are much easier to understand.
And of course, have a http://i993.photobucket.com/albums/af59/Chriss_Rauda/cookie.gif.