What does 'foo' really mean?

Question

I hope this qualifies as a programming question, as in any programming tutorial, you eventually come across 'foo' in the code examples. (yeah, right?)

what does 'foo' really mean?

If it is meant to mean nothing, when did it begin to be used so?

Answer 1

See: RFC 3092: Etymology of "Foo", D. Eastlake 3rd et al.

Quoting only the relevant definitions from that RFC for brevity:

2. Used very generally as a sample name for absolutely anything, esp. programs and files (esp. scratch files).

3. First on the standard list of metasyntactic variables used in syntax examples (bar, baz, qux, quux, corge, grault, garply, waldo, fred, plugh, xyzzy, thud). [JARGON]

Answer 2

foo is used as a place-holder name, usually in example code to signify that the object being named, or the choice of name, is not part of the crux of the example. foo is often followed by bar, baz, and even bundy, if more than one such name is needed. Wikipedia calls these names Metasyntactic Variables. Python programmers supposedly use spam, eggs, ham, instead of foo, etc.

There are good uses of foo in SA.

I have also seen foo used when the programmer can't think of a meaningful name (as a substitute for tmp, say), but I consider that to be a misuse of foo.

Answer 3

As definition of "Foo" has lot's of meanings:

• bar, and baz are often compounded together to make such words as foobar, barbaz, and foobaz. www.nationmaster.com/encyclopedia/Metasyntactic-variable

• Major concepts in CML, usually mapped directly onto XMLElements (to be discussed later). wwmm.ch.cam.ac.uk/blogs/cml/

• Measurement of the total quantity of pasture in a paddock, expressed in kilograms of pasture dry matter per hectare (kg DM/ha) www.lifetimewool.com.au/glossary.aspx

• Forward Observation Officer. An artillery officer who remained with infantry and tank battalions to set up observation posts in the front lines from which to observe enemy positions and radio the coordinates of targets to the guns further in the rear. members.fortunecity.com/lniven/definition.htm

• is the first metasyntactic variable commonly used. It is sometimes combined with bar to make foobar. This suggests that foo may have originated with the World War II slang term fubar, as an acronym for fucked/fouled up beyond all recognition, although the Jargon File makes a pretty good case ... explanation-guide.info/meaning/Metasyntactic-variable.html

• Foo is a metasyntactic variable used heavily in computer science to represent concepts abstractly and can be used to represent any part of a ... en.wikipedia.org/wiki/FOo

• Foo is the world of dreams (no its not) in Obert Skye's Leven Thumps series. Although it has many original inhabitants, most of its current dwellers are from Reality, and are known as nits. ... en.wikipedia.org/wiki/Foo (place)

• Also foo’. Representation of fool (foolish person), in a Mr. T accent en.wiktionary.org/wiki/foo

Resource: google

Answer 4

It's a metasyntactic variable.

Answer 5

foo = File or Object. It is used in place of an object variable or file name.

Answer 6

I think it's meant to mean nothing. The wiki says:

"Foo is commonly used with the metasyntactic variables bar and foobar."

Answer 7

The sound of the french fou, (like: amour fou) [crazy] written in english, would be foo, wouldn't it. Else furchtbar -> foobar -> foo, bar -> barfoo -> barfuß (barefoot). Just fou. A foot without teeth.

I agree with all, who mentioned it means: nothing interesting, just something, usually needed to complete a statement/expression.

Answer 8

Among my colleagues, the meaning (or perhaps more accurately - the use) of the term "foo" has been to serve as a placeholder to represent an example for a name. Examples include, but not limited to, yourVariableName, yourObjectName, or yourColumnName.

Today, I avoid using "foo" and prefer using this type of named substitution for a couple of reasons.

• In my earlier days, I originally found the use of "foo" as a placement in any example to represent something as f'd-up to be confusing. I wanted a working example, not something that was foobar.
• Your results may vary, but I always, 100%, everytime, never-failed, got more follow-up questions about the meaning of the actual variable where "foo" was used.

Answer 9

In my opinion every programmer has his or her own "words" that is used every time you need an arbitrary word when programming. For some people it's the first words from a childs song, for other it's names and for other its something completely different. Now for the programmer community there are these "words" as well, and these words are 'foo' and 'bar'. The use of this is that if you have to communicate publicly about programming you don't have to say that you would use arbitratry words, you would simply write 'foo' or 'bar' and every programmer knows that this is just arbitrary words.