The document discusses the evolution and benefits of magazine flaps, which are partial pages that wrap around or are glued to the spine of magazines. Magazine flaps first started appearing in publications like The New Yorker in the 1990s and became more common around 2000. They provide extra space to promote the issue's content without covering the front cover. Flaps can now be personalized for each reader with their name and targeted ads. Publishers collaborate by selling ad space on flaps while magazines define their audiences for tailored promotions.