When you use rlogin or telnet to login to the shell, you can use command-line editing. Command-line editing lets you access commands from your history file, edit them, and run the result. You have already seen this process before, when reading about some of the features of the r command.

Command editing is useful at those times when you are running the same sequence of commands, or slight variations on the same sequence of commands. The point of command editing is to save yourself the trouble of typing the same thing over and over again—look especially for long commands that normally require a lot of typing. Command editing is also useful when you have made a mistake in typing a command line and wish to correct it.