1. To wait for an event that will never occur. "The system is
hanging because it can't read from the crashed drive". See
2. To wait for some event to occur; to hang around until
something happens. "The program displays a menu and then
hangs until you type a character." Compare
block.
3. To attach a peripheral device, especially in the
construction "hang off": "We're going to hang another tape
drive off the file server." Implies a device attached with
cables, rather than something that is strictly inside the
machine's chassis.