.BAK File extension

A BAK file is a backup of the Firefox bookmarks file, which can be used to replace saved bookmarks in case the main bookmarks file becomes corrupted. It is automatically generated by the Firefox web browser and typically named "bookmarks.bak".

The bookmarks.bak file is located in the following directories on Windows and Macintosh systems:

• Windows - C:\Documents and Settings\UserName\Application Data\MozillaFirefox\Profiles\[random-name]
• Mac - /Users/[username]/Library/Application Support/Firefox/Profiles/[random-name].default