The classic pin-up girl is more than simply a painting of a curvy woman. Pin-up girls capture the essence of a time when even the scant baring of skin was considered exotic and risque.

A pin-up girl, also known as a pin-up model, is a model whose mass-produced pictures see wide appeal as popular culture. Pin-ups are intended for informal display, e.g. meant to be « pinned-up » on a wall. Pin-up girls may be glamour models, fashion models, or actresses.

The pin-up images could be cut out of magazines or newspapers, or be from postcard or chromo-lithographs, and so on. Such photos often appear on calendars, which are meant to be pinned up anyway. Later, posters of pin-up girls were mass-produced and became an instant hit. As social standards changed, male subjects began to be featured in pin-ups also.