There has never been a time when the female figure wasn't the subject of art. What distinguishes Pin-up Art from the rest is the very reason it soared to popularity during a time that made its existence possible. The hallmark of Pin-up Art is that it portrays contemporary women (and, eventually, men) baring just the right amount of skin to be deemed suitable for both mass production and public display.
First came the modern printing press and its ability to mass produce images that were once accessible to only a select few. The second criteria of Pin-up Art—it's suitability for display—is an ever-changing target that mirrors societal standards. In the 1800s, even baring an ankle was scandalous, but by the time mass printing became affordable, society had adopted a more liberal perspective on contemporary women's sexuality, albeit one with boundaries. The pin-up girl might bare her stockings, but her thigh often was the limit. Pin-up Art must strike a delicate note that raises eyebrows without sounding alarms, toeing the line between what is deemed provocative but not pornographic.
The popularity of Pin-up Art exploded during World War II, when soldiers "pinned up" images of their favorite women–models and actresses, but often women they knew from home, the workforce, or the military–on their trunks, lockers and even tanks and planes. These images were photographs or artwork frequently torn from the pages of magazines, but also often sent to them by real women in their lives, who were emboldened to express themselves sexually as new responsibilities in the war led them to feel more confident professionally. Pin-up Art also appeared on calendars—designed to to be "pinned up." Pin-up Art is frequently referred to as "cheesecake," based on the legend that one man feasted his eyes on a photo of a bombshell in a particularly fetching pose and exclaimed, "Why, this is better than cheesecake!" It's also where we derive the term for the pin-up girl's male counterpart: beefcake.
A genre that continues to thrive and evolve, Pin-up Art has been thoroughly debated by the feminist movement that was born and has evolved along the same timeline as the Pin-up genre. Its detractors condemn the appeal of many conventional pin-ups' objectification of women's sexuality. But its feminist supporters note that many actually represent quite the opposite: pin-up girls are often depicted as self-aware, assertive, strong, and independent. At their best, such images are less about representing women seducing men than their embracing and celebrating their own sexuality, unapologetically, as a powerful and integral part of their whole being. This perspective on the genre's feminist potential was arguably summed up by one of the most popular WWII pin-up girls, Betty Grable, who joked of her generation's growing boldness, "The practice of putting women on pedestals began to die out when it was discovered that they could give orders better from there."