Inserting Question Marks in Cisco IOS CLI

Question marks can be inserted into literal strings, eg: interface descriptions, by typing CTRL+V immediately before the question mark. It acts as an escape sequence and prevents the command line from summoning the context-sensitive help menu.

Router#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#int fa0/0
Router(config-if)#desc ### Testing[CTRL+V]? ###
Router(config-if)#
Router(config-if)#do sh int desc
Interface                      Status         Protocol Description
Fa0/0                          admin down     down     *** Testing? ***
Router(config-if)#