A wildcard character is a special character that represents one or more other characters. The most commonly used wildcard characters are the asterisk (*), which typically represents zero or more characters in a string of characters, and the question mark (?), which typically represents any one character. For example, in searching:
run*would mean "any word that starts with 'run' and has any kind of ending." If you entered "run*" at a search engine that offered a wildcard character capability, you would get results for run, runs, running, runner, runners - in short, any possible word that might begin with the three letters.
Wildcard characters are used in regular expressions (a form of programming in which input data is modified based on specified patterns) and in searching through file directories for similar file names (for example, if all the work files on a project start with the characters "P5," you could easily locate all the project files by simply searching for "P5*").
A wildcard character is a type of meta character . In various games of playing cards, a wild card is a designated card in the deck of cards (for example, the two of spades) that can be used as though it were any possible card.