Pin-up refers to a model whose mass-produced images see wide appeal as popular culture. The aesthetic is characterized by a playful and glamorous portrayal of sexuality, often with a nostalgic, mid-20th-century feel. Although the term "pin-up" was not coined until 1941, its origins can be traced to earlier forms of glamour art and photography. The style is most associated with female models, often called "cheesecake," but also includes male models, known as "beefcake."

Pin-up images are intended to be "pinned up" on a wall and typically feature models in alluring, often romanticized poses. The aesthetic ranges from innocent and playful to more explicitly suggestive and fetish-oriented themes. In modern times, the pin-up style has been embraced as a form of empowerment, celebrating confidence, beauty, and ownership of one's sexuality, famously embodied by figures like Marilyn Monroe and Bettie Page.

The modern pin-up aesthetic began to take shape in the 1920s and 30s, evolving from early burlesque advertisements and the illustrative work of artists like Alberto Vargas, whose idealized paintings of women became known as "Vargas Girls." During this period, Black bombshells like Josephine Baker and Dorothy Dandridge also became influential figures, carving out their own space in the glamour and entertainment industries.

The style exploded in popularity during World War II, when mass-produced images of glamorous women, most famously Betty Grable, were distributed to American soldiers to boost morale. These wartime pin-ups typically portrayed a wholesome, "girl-next-door" appeal, even when posed in swimsuits or lingerie. After the war, the aesthetic began to diverge. The 1950s saw the rise of a more explicit and fetish-oriented style, largely driven by the founding of Playboy magazine in 1953 and the meteoric rise of model Bettie Page. Known as the "Queen of Bondage," Page's work with photographers like Bunny Yeager introduced themes of BDSM and fetishism to a mainstream audience, cementing her status as a counter-cultural icon.

The Pin-up aesthetic is defined by a highly stylized and glamorous look that emphasizes classic femininity and allure. Makeup is a key component, characterized by a flawless complexion, shaped eyebrows, sharp black winged eyeliner, and vibrant red lipstick applied in a "hunter's bow" shape. Hairstyles are equally iconic, with popular styles including victory rolls, barrel curls, and "Bettie bangs"—a short, blunt fringe.

Fashion ranges from playful to provocative. Common clothing items include high-waisted shorts, pencil skirts, sailor-themed outfits, and circle dresses, often featuring patterns like polka-dots, cherries, or leopard print. Lingerie, including garter belts, stockings, and corsets, is also central to the aesthetic. The overall silhouette aims to accentuate an hourglass figure. In modern interpretations, tattoos are often incorporated into the classic pin-up look.

The Pin-up aesthetic has been defined by numerous models, artists, and photographers throughout its history.

The glamour and playful sensuality of the pin-up style have influenced numerous musicians. Marilyn Monroe's performance of " Diamonds Are a Girl's Best Friend " is an iconic example from the era. In later decades, artists like Madonna (" Material Girl ") and Britney Spears (" Lucky ") have drawn heavily on the pin-up aesthetic in their music videos and styling.