Firefox bookmarks
Firefox bookmarks originally used the HTML-based Netscape bookmarks format, as did the Mozilla/Seamonkey Suite. However, as of Firefox 3.0, a new format was used based on SQLite with write-ahead logging. The bookmarks are also regularly automatically backed up in the JSON format.
The relevant files are places.sqlite and places.sqlite-wal in the user profile directory (system-specific; in Windows Vista it is \Users\username\AppData\Roaming\Mozilla\Firefox\Profiles\cryptic-profile-ID). This directory structure may be hidden depending on your operating system configuration. A subdirectory of this called bookmarkbackups has the backups, with filenames like bookmarks-2012-10-28.json which contain the date of the backup.
The data structure in the SQLite file is given in the embedded command CREATE TABLE moz_bookmarks (id INTEGER PRIMARY KEY,type INTEGER, fk INTEGER DEFAULT NULL, parent INTEGER, position INTEGER, title LONGVARCHAR, keyword_id INTEGER, folder_type TEXT, dateAdded INTEGER, lastModified INTEGER, guid TEXT).
