引言
今天看 SaltStack Manual时，里面的例子使用了 foo/bar 来说明，联想到之前在不少编程书籍和文章中也看到了这对 foo/bar，很好奇它们的来源。
foo bar 来源不简单
比我好奇的人更多，已经有很多人都寻找 foobar 的来源了，这里我们就直接来看看吧。
The terms foobar (/ˈfuːbɑːr/), or foo and others are used as placeholder names (also referred to as metasyntactic variables) in computer programming or computer-related documentation.[1] 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.
