Based on a pin-up photo of Dusty Anderson for the Oct. 27, 1944 issue of Yank, the Army Weekly, a weekly U.S. Army magazine fully staffed by enlisted men.
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, i.e. meant to be “pinned-up” on a wall. Pin-up girls may be glamour models, fashion models, or actresses. The term pin-up may also refer to drawings, paintings, and other illustrations done in emulation of these photos. The term was first attested to in English in 1941; however, the practice is documented back at least to the 1890s. 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. (source: Wikipedia.org)