The wiki description of Swimsuit:
A swimsuit, bathing suit, swimming costume, tog, bather, or cossie (short for "costume") is an item of clothing designed to be worn by men, women or children while they are engaging in a water-based activity or water sports, such as water polo, diving, swimming, surfing, water skiing or even sun bathing.
A swimsuit can be worn as an undergarment in sports that require a wetsuit such as water skiing, scuba diving, surfing, wakeboarding among others. Swimsuits are also worn when there is a need to display the body, as in the case of bodybuilding contests and beauty pageants. Some photography and magazines like the annual Sports Illustrated Swimsuit Issue feature models and sports personalities in swimsuits.
There is a very wide range of styles of modern swimsuits, which vary in relation to body coverage and materials. The choice of style of swimsuit is dependent on current fashions and community standards of modesty, religious beliefs as well as on personal preferences.