Bucky bit

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In computing, a bucky bit is a bit in a binary representation of a character that is set by pressing on a keyboard modifier key other than the shift key.

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Overview

Setting a bucky bit changes the output character. A bucky bit allows the user to type a wider variety of characters and commands while maintaining a reasonable number of keys on a keyboard.

Some of the keys corresponding to bucky bits on modern keyboards are the alt key, control key, meta key, command key (⌘), super key, and option key.

In ASCII, the bucky bit is usually the 8th bit (also known as meta bit). However, in older character representations wider than 8 bits, more high bits could be used as bucky bits. In the modern X Window System, bucky bits are bits 18–23 of an event code. [1]

History

The term was invented at Stanford and is based on Niklaus Wirth's nickname "Bucky". Niklaus Wirth was first to suggest an EDIT key to set the eighth bit of a 7-bit ASCII character sometime in 1964 or 1965. [2]

Bucky bits were used heavily on keyboards designed by Tom Knight at MIT, including space-cadet keyboards used on LISP machines. These could contain as many as seven modifier keys: SHIFT , CTRL , META , HYPER, SUPER , TOP, and GREEK (also referred to as FRONT). [1] [3]

See also

Related Research Articles

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The keyboard for IBM PC-compatible computers is standardized. However, during the more than 30 years of PC architecture being frequently updated, many keyboard layout variations have been developed.

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In computing, a modifier key is a special key on a computer keyboard that temporarily modifies the normal action of another key when pressed together. By themselves, modifier keys usually do nothing; that is, pressing any of the ⇧ Shift, Alt, or Ctrl keys alone does not (generally) trigger any action from the computer.

Control key Key on computer keyboards

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A dead key is a special kind of modifier key on a mechanical typewriter, or computer keyboard, that is typically used to attach a specific diacritic to a base letter. The dead key does not generate a (complete) character by itself, but modifies the character generated by the key struck immediately after. Thus, a dedicated key is not needed for each possible combination of a diacritic and a letter, but rather only one dead key for each diacritic is needed, in addition to the normal base letter keys.

Keyboard shortcut Series of computer keys to quickly invoke a software program or perform a preprogrammed action

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Space-cadet keyboard Keyboard used on MIT Lisp machines, influential to Emacs

The space-cadet keyboard is a keyboard designed by John L. Kulp in 1978 and used on Lisp machines at Massachusetts Institute of Technology (MIT), which inspired several still-current jargon terms in the field of computer science and influenced the design of Emacs. It was inspired by the Knight keyboard, which was developed for the Knight TV system, used with MIT's Incompatible Timesharing System.

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Alt key Computer key

The Alt keyAlt on a computer keyboard is used to change (alternate) the function of other pressed keys. Thus, the Alt key is a modifier key, used in a similar fashion to the Shift key. For example, simply pressing A will type the letter 'a', but holding down the Alt key while pressing A will cause the computer to perform an Alt+A function, which varies from program to program. The international standard ISO/IEC 9995-2 calls it Alternate key. The key is located on either side of the space bar, but in non-US PC keyboard layouts, rather than a second Alt key, there is an 'Alt Gr' key to the right of the space bar. Both placements are in accordance with ISO/IEC 9995-2. With some keyboard mappings, the right Alt key can be reconfigured to function as an AltGr key although not engraved as such.

Meta key Modifier key on workstation keyboards of the 1970s/80s

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The Command key, , formerly also known as the Apple key or open Apple key, is a modifier key present on Apple keyboards. The Command key's purpose is to allow the user to enter keyboard commands in applications and in the system. An "extended" Macintosh keyboard—the most common type—has two command keys, one on each side of the space bar; some compact keyboards have one only on the left.

Esc key Computer key

On computer keyboards, the Esc keyEsc is a key used to generate the escape character. The escape character, when sent from the keyboard to a computer, often is interpreted by software as "stop", and when sent from the computer to an external device marks the beginning of an escape sequence to specify operating modes or characteristics generally.

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On personal computers with numeric keypads that use Microsoft operating systems, such as Windows, many characters that do not have a dedicated key combination on the keyboard may nevertheless be entered using the Alt code. This is done by pressing and holding the Alt key, then typing a number on the keyboard's numeric keypad that identifies the character and then releasing Alt.

Super key (❖) is an alternative and older name for what is commonly labelled as the Windows key or Command key on modern keyboards, typically bound and handled as such by Linux and BSD operating systems and software today.

Emacs Family of text editors

Emacs or EMACS is a family of text editors that are characterized by their extensibility. The manual for the most widely used variant, GNU Emacs, describes it as "the extensible, customizable, self-documenting, real-time display editor". Development of the first Emacs began in the mid-1970s, and work on its direct descendant, GNU Emacs, continues actively as of 2022.

Keyboard layout Arrangement of keys on a typographic keyboard

A keyboard layout is any specific physical, visual or functional arrangement of the keys, legends, or key-meaning associations (respectively) of a computer keyboard, mobile phone, or other computer-controlled typographic keyboard.

References

  1. 1 2 Raymond, Eric S.; Cameron, Debra; Rosenblatt, Bill (1996). Learning GNU Emacs, 2nd Edition. Sebastopol, CA: O'Reilly. pp. 408–409. ISBN   1-56592-152-6.
  2. The Jargon File. Xinware Corporation. 2007. p. 128. ISBN   978-1-897454-66-4.
  3. "Space Cadet keyboard". home.comcast.net. Archived from the original on 6 September 2015. Retrieved 12 January 2022.