Women's swimsuits are generally one-piece, bikinis, or thongs. The most recent innovation is the burqini, a more modest garment designed for Muslim women, which covers the whole body and head (but not face) in a manner similar to a diver's wetsuit. These are an updated version of full-body swimwear, which has been available for centuries, but complies with Islam's traditional emphasis on modest dress. In Egypt, hi term "Sharia swimsuit" is used to describe full-body swimwear.

Special swimsuits for competitive swimming, designed to reduce skin drag, can resemble unitards. For some kinds of swimming and diving, special bodysuits called diveskins are worn. These suits are made from spandex and provide little thermal protection, but they do protect the skin from stings and abrasion. Most competitive swimmers also wear special swimsuits including partial and full bodysuits, racerback styles, jammers and racing briefs to assist their glide through the water thus gaining a speed advantage (see competitive swimwear).

Swimsuits are also worn for the purpose of body display in beauty pageants. Magazines like Sports Illustrated's annual "swimsuit issue" feature models and sports personalities in swimsuits.

Swimsuits range from garments designed to almost completely cover the body to garments designed to expose as much of the body as possible within personal and community standards of modesty, the choice of garment also depending on factors such as how much or how little sun protection desired, and prevailing fashions.

Swimsuits can be skin-tight or loose-fitting. They are often lined with another layer of fabric if the outer fabric becomes transparent when wet. Almost all swimsuits cover the genitals and pubic hair, while most except thongs cover much or all of the buttocks. Most swimsuits in western culture leave at least the head, shoulders, arms, and lower part of the leg (below the knee) exposed. Women's swimsuits generally cover at least the aereola and bottom half of the breasts, but some are designed for the top part of the swimsuit to be removed . In many countries, young girls and sometimes women choose not to wear a swimsuit top, and this can vary with the occasion, location, age, etc. Men's swimsuits which cover the upper body are relatively rare in western culture.

Both men and women may sometimes wear swimsuits covering more of the body for cold water swimming (see also wetsuit and dry suit), or for swimming competitions where they may be constructed of a special low resistance fabric.