Meta bit
The top bit of an 8-bit character, which is on in character values 128--255.
Also called high bit, alt bit, or hobbit.
Some terminals and consoles (see space-cadet keyboard) have a META shift key.
Others (including, *mirabile dictu*, keyboards on IBM PC-class machines) have an ALT key.
See also bucky bits.
Historical note: although in modern usage shaped by a universe of 8-bit bytes the meta bit is invariably hex 80 (octal 0200), things were different on earlier machines with 36 bit words and 9-bit bytes.
The MIT and Stanford keyboards (see space-cadet keyboard) generated hex 100 (octal 400) from their meta keys.
[Jargon File]
| < Previous Terms | Terms Containing meta bit | Next Terms > |
| Messaging Applications Programming Interface mess-dos META meta META 5 | alt bit double bucky dread high bit disease high bit hobbit | MetaCard Meta-CASE tool Metaclass Meta-Crystal Metadata |
