In various Teenage Mutant Ninja Turtles comic books, pin-ups are assorted sketches and artworks printed as part of an issue, usually in the back pages and sometimes accompanying a letters page. The pin-ups could show random or frivolous scenes, sometimes completely disconnected from the issue's story. They were historically common in Eastman and Laird's Teenage Mutant Ninja Turtles and associated publications by Mirage Studios, and could also be encountered in Teenage Mutant Ninja Turtles Adventures by Archie Comics. In modern times, pin-ups have become far less common in TMNT comic books, especially as it has become more common for comic artists to self-publish sketches and promotional work on the internet, a resource which was not previously widely accessible to the general public until the mid-1990s. Pin-ups are particularly scarce in Teenage Mutant Ninja Turtles by IDW Publishing, which began its publication run in 2011, when many of its artists were already well-established on social media platforms and digital art communities.