A wildcard character is a keyboard character such as an asterisk (*) or a question mark (?) that is used to represent one or more characters when you are defining a filter. Wildcard characters are often used in place of one or more characters when you do not know what the real character is or you do not want to type the entire name.
Uses:
Use the asterisk as a substitute for zero or more characters. If you are looking for a name that you know starts with "win" but you cannot remember the rest of the name, type the following: win*. This locates all names that begin with "win" including Windows, Winner, and Wind.
Use the question mark as a substitute for a single character in a name. For example, if you type win?, you will locate Wind but not Windows or Winner.