The question mark (?) is almost always used in Cisco IOS to present the help context menu. However, it can also be used as a special character in regex strings and EEM scripts. It can also be used in meta-information fields such as a VLAN name or interface description though I would considered it best to avoid this practice (but someone always has a “good” reason for everything). Should you ever have the need to insert a question mark (?), the escape sequence Ctrl + V must first be entered then the question mark (?) can be inserted as a string character.