Boy shorts

Panties in American English (typically called knickers in British English) are a form of underwear worn by women. Panties are most often form-fitting, but may also be loose. Typical components include an elastic waistband, a crotch panel to cover the genital area (usually lined with absorbent material such as cotton), and a pair of leg openings that, like the waistband, are often made of elastic. Various materials are used, but are usually chosen to be breathable.

Panties were originally designed to cover the entire lower half of the female torso, since the 1970s panties have had either no legs or, in some cases, very short ones, and have become increasingly briefer over time.

In countries such as the United Kingdom (UK), Ireland, South Africa, and occasionally in other Commonwealth countries such as Australia and New Zealand, panties are often referred to as "knickers" or "undies". In Australia, men's underpants are often referred to as "undies". The term is little used in the United States (US) and Canada, where the term "panties" is usually favoured. In the UK, the term "pants" is also used for both men and women's underwear (not to be confused with the North American usage of pants, which refer to what both Americans and the British call "trousers", although this term is also used in some parts of Northern England).

Panties are classified into various styles based on criteria such as the amount of rear coverage, width at the sides and height at which they are worn. These categories are not necessarily distinct and usage may vary somewhat among brands:

...
Wikipedia