From The Art and Popular Culture Encyclopedia
Cover art is the illustration or photograph on the outside of a published product such as a book, magazine, comic book, product package, video game, DVD, CD, videotape, audio album, manual or brochure.
One type of cover art is that of CDs or DVDs. Most notable of this category would be album art, referring specifically to artwork created for a music album. Among the most noted are those by Pink Floyd, especially The Dark Side of the Moon and Wish You Were Here, and The Beatles' Sgt. Pepper's Lonely Hearts Club Band.
For comic books, the cover art has historically been considered a main selling point. Great effort was put into the covers in order to attract readers. However, Marvel Comics Executive Editor Tom Brevoort has commented that there has been a shift in the industry and the cover art is no longer the primary advertising tool.