What wears a jacket but no pants?

This clever riddle points to a common item found in many homes and libraries: a book. Specifically, it refers to the "dust jacket" or "book jacket" that often adorns hardcover editions. This detachable outer cover, usually made of paper, wraps around the more permanent binding of the book, much like a jacket worn by a person.

The primary purpose of a book jacket is to protect the actual book covers from damage, dust, scratches, and wear. Early dust jackets, appearing as far back as the late 18th and early 19th centuries, were often plain and simply served as protective wrappers to safeguard the often ornate or delicate bindings underneath during transit and storage. The oldest known publisher's dust jacket dates to 1829. Over time, their role evolved significantly.

Beyond protection, the book jacket became a crucial marketing tool. Publishers realized its potential as a canvas for artistic expression, using vibrant designs, illustrations, and typography to attract potential readers. The jacket often includes the book's title, author's name, a compelling summary or "blurb," and biographical information about the author on its flaps, all designed to entice someone browsing a bookstore.

While modern printing technologies allow for direct printing onto the hardcover itself, dust jackets remain a cherished element, enhancing a book's aesthetic appeal and providing valuable promotional content. They offer a first impression, beckoning readers to explore the stories within, and are often preserved by collectors and libraries for their aesthetic and informational value.