Pin-up girls or Pin-up Models, made their debut as early as the 1890's, although I'm sure back then it was seen as a very 'Trampish' career choice.
One of the most popular early pin-up girls was Betty Grable, whose poster was ubiquitous in the lockers of G.I.s during World War II.
|Betty Grable's world-wide famous 1943 pin-up photo,|
that showed off those "million dollar legs."
Today it's used in media all the time from Illustrations to Photos.
Here are some of my favourites...