This wonderful little command saved the DOS BAT gurus from having to put an '@' symbol in front of every line of the script to prevent the line from being displayed. Echo off was always the first line of the BAT script, and therefore had to have an '@' symbol in front of it to stop it from showing up on the screen.

In the days of DOS and cute fuzzy file managers this was the command that determined your level of l33tness. That, and it just made everything look so tidy ...