Metasyntactic variable

Metasyntactic variables used commonly across all programming languages include foobar, foo, bar, baz, qux, quux, corge, grault, garply, waldo, fred, plugh, xyzzy, and thud.

[6] In France, the word toto is widely used, with variants tata, titi, tutu as related placeholders.

[citation needed] In Turkey, the words hede and hödö (usually spelt hodo due to ASCII-only naming constraints of programming languages) are well-known metasyntactic variables that stem from popular humorous cartoon magazines of the 90's like LeMan.

The terms were popularized more widely by the actor and stand-up comedian Cem Yılmaz in the late 90's and early 2000's.

These names often appear in pseudo-code, are referenced in software engineering classes, and are commonly employed when explaining algorithms to colleagues.

Both the IETF RFCs and computer programming languages are rendered in plain text, making it necessary to distinguish metasyntactic variables by a naming convention, since it would not be obvious from context.

[13] It is common to use the name ACME in example SQL databases and as a placeholder company-name for the purpose of teaching.