Wildcards have been around forever. Some even claim they appear in the hieroglyphics of the ancient Egyptians. Wildcards allow you to specify succinctly a pattern that matches a set of filenames (for example, *.pdf to get a list of all the PDF files). Wildcards are also often referred to as glob patterns (or when using them, as "globbing"). But glob patterns have uses beyond just generating a list of useful filenames. The bash man page refers to glob patterns simply as "Pattern Matching".