A pamphlet is an unbound booklet (that is, without a hard cover or binding). It may consist of a single sheet of paper that is printed on both sides and folded in half, in thirds, or in fourths (called a leaflet), or it may consist of a few pages that are folded in half and stapled at the crease to make a simple book. Librarians consider a pamphlet to be any paperback book with 49 pages or less, that is not aimed at children.

Pamphlets can contain anything from information on kitchen appliances to medical information to religious treatises. Pamphlets are very important in marketing as they are cheap to produce and can be distributed easily to customers. Pamphlets have also long been an important tool of political protest for similar reasons.

The storage of individual pamphlets requires special consideration because they can be easily crushed or torn when shelved alongside hardcover books. For this reason, they should either be kept in file folders in a file cabinet, or kept in boxes that have approximately the dimensions of a hardcover book and placed vertically on a shelf.