SGML/XML based format which is particularly well suited to books and papers about computer hardware and software
can store not only a documentation, but also general books and articles, web-sites, slides, thesis, …
open and platform neutral
stable—DocBook is used and developed since 1991
standardized—DocBook development is done under OASIS
DocBook users: software vendors (Novell, Sun, HP), publishing houses (O'Reilly), open-source projects (Linux, FreeBSD, PHP, RedHat, …)