Originally a CLI mask for filenames that used two 'anything' characters in order to narrow your selection of a file name.
- * (star) meaning any number of any possible characters (including zero characters; nothing).
- ? (question mark) meaning only one character of any possible characters (not including zero characters).
For example, f*uck could mask FireTruck. Whereas f?uck could mask ftuck
These days it's a more generic concept of describing similar things. Such as *nix describing not just the character pattern but anything like Unix. BSD or Linux, for example.