Foo Bar

MIT AI Lab in the 1960s published technical reports containing program code.

The military slang ‘FUBAR’ f’ed up beyond all recognition, was in the student and professor engineering vocabulary. The tradition became to use ‘fu’ and ‘bar’ as nominal function names, in same manner as X and Y were nominal variables.

Often in the MIT technical reports, one would see x = fu(y) or y > bar(z) and so forth.

A few years later, perhaps with the welcome progress of more female faculty and students, textbooks changed the spelling, but not the pronunciation of the vulgar acronym ‘fu’ to ‘foo’.

Foobar is used as metasyntactic variables and placeholder names in computer programming or computer-related documentation. They have been used to name entities such as variables, functions, and commands whose exact identity is unimportant and serve only to demonstrate a concept.

Stackoverflow has a good answer on the origin of foo and bar. (webarchive)