Compression shorts are specialized apparel designed to give more support to athletes and people engaging in physical activity. When people engage in strenuous physical activity, such as most sports, the muscles in the thighs and the muscles in the groin rub each other, causing friction. This results in two things: skin chafing and irritation of the sciatic nerve. The sciatic nerve is located on the outside of the thigh, and when irritated, can cause pain. The main objective of wearing compression shorts is to separate the muscles in the groin and and thighs to avoid those two problems.
Compression shorts are often made of nylon and lycra. The nylon in the material offers the possibility of a comfortable fit, and adds the benefit of cooling the skin as well. The lycra, on the other, serves the purpose of providing a bit of compression and support. There are even specialized materials which have been specially formulated to draw away the sweat from the inside to the outside of the shorts. This gives the added benefit of keeping the skin dryer than when you wear normal clothing.
If you are having a difficult time envisioning what compression shorts look like, think of the common outfit of cyclists. They wear tight-fitting cycling shorts - those are actually a form of compression shorts! There are many kinds of compression shorts being sold by a variety of manufacturers today, both for men and women. You only have to take a look to see what style and material suit your needs and preferences best.