On the login to the first timesharing system I used, it would prompt for your password, then type eight M's, W's, and X's on top of each other (on paper, of cou

On the login to the first timesharing system I used, it would prompt for your password, then type eight M's, W's, and X's on top of each other (on paper, of course, since this was using a Teletype terminal), so when you actually typed your password the characters would be printed on top of those already obscured lines.