There really are some file formats that have “mad” in their name or extension. Some people may find this blog when trying to learn about them, so I suppose I should provide some information about them.
There’s MadTracker, which is music composition software. The Archive Team page (also known as “Just Solve the File Format Problem”) has a page on the MadTracker 2 module format. It’s a stub, but it mentions five other MadTracker formats.
There are Microsoft Access Module Shortcut files, which have the extension .MAD for no obvious reason.
Electronic Arts Madcow movie files have the extension .MAD. Several Electronic Arts games use the format.
MariaDB stores a database in a file with the .MAD extension.
There are some scattered references to Model Animation Data files used in Homeworld games, and there’s a Magic Album Deck which is used in computer-assisted Magic: The Gathering. Both use the .MAD extension.
The Library of Congress has the Metadata Authority and Description Schema, or MADS. It’s used with MODS, the Metadata Object Description Schema.
Finally, there’s an old programming language called Michigan Algorithm Decoder. The compiler printed out a picture of Alfred E. Newman with each error dump.
There are probably more, but that’s what I can find with a reasonable amount of searching.