Booklets are small books, usually having a paper cover.
This term can also be used as a synonym for "flyer" or "leaflet" in most cases. However, the term "booklet" usually implies more than one page. In the past decades, booklets became widely known as the companion to CD or DVD media, the famous CD booklets and DVD booklets. As you know, there are various sizes and possible structures and folds. As pieces to be included inside CD or DVD cases, these booklets are usually printed on high quality stock, and their morphology allows eye-catching, impressive designs.