Razor bumps and razor burns are two distinct types of skin irritation caused by shaving. Both are completely avoidable if you use the proper shaving technique.
Razor burn is caused by removal of surface skin cells, either by pressing too hard with a razor or going over an area too many times. You've skinned yourself.
Razor bumps are caused by ingrown hairs, which are in turn caused by a close shave. Curly hair is more prone to shaving bumps than straight hair; hence women’s use of depilatories and waxing around the bikini lines.
Shaving with the grain—downward, in the direction of hair growth—prevents bumps. Using a lighter touch, or a cartridge razor with a swiveling head, prevents burn.
A wetter shave allows a razor to glide more smoothly. Someone prone to burns or bumps should try a wet shave after a bath or shower. Use shave oil as a base, then shaving soap on top of the oil and then the technique described in Section 3.
Burns can be remedied by using a cream-based, alcohol-free shaving balm. Bumps are, in essence, pimples, which will go away on their own in several days or will respond to acne creams.