interface: Just like on a typewriter, the Mac's Return key ends one line and starts another. Wierdly called "carriage return" by some people who seem to not realize that computers don't have paper carriages. In dialog boxes, typing Return will often perform the default action, such as opening the selected file in an Open dialog. In telecommunications, you sometime must type Return at the end of every command in order to send it, and often insert a return character after every 80 (or fewer) characters. A return character is often used as a delimiter (separator) of whole records in a database or lines in a spreadsheet when exporting.