In binding and finishing, a thin ribbon or cord fastened at the top of a book's spine under the backlining, designed as a decorative ornament on specialty books or deluxe editions. The term book mark also refers to any material inserted into a book—usually by a reader—to mark one's place, including the dogear.
In multimedia and World Wide Web applications, a book mark (usually spelled as one word, bookmark') is an electronic marker added to an application program. On a CD-ROM, for example, a marker can be added at certain points, given a name, and selected again at a later time from a menu, allowing the user to go directly to that point in the presentation. Bookmarks are also used in Web browsers, where they are essentially a type of alias, or a stored URL, allowing the user to go directly to a web site without having to enter often unwieldy addresses.