Stylized line drawing of mark playing the flute

Foo, bar, and other metasyntactic variables

Anyone who deals with code for a living has come across foo or bar as a placeholder. You may have even cursed someone who used it as a permanent name, leaving you to decipher the intent.

A few more of you may have heard of, or even used, baz.

But it doesn’t end there!

The β€œstandard” list for English is:


Originally a nonsense word from the 1930s comic Smokey Stover and a military shorthand for FUBAR in the 1940s, it gained popularity in computing with the Tech Model Railroad Club at MIT in the 1960s.


Another shorthand for FUBAR from WWII.


According to the Jargon File 4'0, baz also originates with the Tech Model Railroad Club and the Pogo character Albert the Alligator.


A mutation of quux.


Coined by American computer scientist Guy Steele. It can be used to imply that a point is not crucial (opposite of crux).


Invented by Mike Gallaher, this gained popularity via the GOSMACS (first implementation of Emacs-in-C) documentation. May be based on the name of someone’s cat.


See corge.


Used by hackers at the Stanford Artificial Intelligence Laboratory (SAIL).


A mechanical device, like an arm, that is controlled by a human limb. They were originally developed for handling nuclear materials in the 1940s and named after the Robert A. Heinlein story of the same name. Popularized by Tom Cheatham and his students at Harvard.


Popularized by its ease of typing as a variable name. May stand for Flipping Ridiculous Electronic Device in some circles.


A magic word from the adventure game ADVENT, a precursor to Adventure.


Another magic word from ADVENT, it teleports the player between two locations.


One of the canonical variables at CMU in the mid-1970s. Sometimes found preceeding blat.

And other languages have their own commonly-used words too.

The etymology of Foo is fascinating in its own right. I wont duplicate the fine efforts of RFC 3092 to document it.

Another weird little bit of computer history.

Additional information:

What is the origin of foo and bar?

Jargon File


Metasyntactic variable