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), [2] [3] [4] which inspired several still-current jargon terms[ citation needed ] 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.
The space-cadet keyboard was equipped with seven modifier keys: four keys for bucky bits ( ⎈ Control , ◆ Meta , ❖ Super , and ✦ Hyper ), and three shift keys, called ⇧ Shift , Top , and Front (which was labeled on the front of the key; the top was labeled Greek ). Meta had been introduced on the earlier Knight keyboard, while Hyper and Super were introduced by this keyboard. [5] Each group was in a row, thus allowing easy chording, or pressing of several modifier keys; for example, Control+Meta+Hyper+Super could be pressed with the fingers of one hand, while the other hand pressed another key.
Many keys had three symbols on them, accessible by means of the shift keys: a letter and a symbol on the top, and a Greek letter on the front. For example, the G key had a "G" and an up-arrow ("↑") on the top, and the Greek letter gamma ("γ") on the front. By pressing this key with one hand while playing an appropriate "chord" with the other hand on the shift keys, the user could get the following results:
| Key pressed | Result |
|---|---|
| G | g (lowercase G) |
| ⇧ Shift+G | G (uppercase G) |
| Front+G | γ (lowercase gamma) |
| Front+⇧ Shift+G | Γ (uppercase gamma) |
| Top+G | ↑ (upwards arrow) |
Each of these might, in addition, be typed with any combination of the ⎈ Control , ◆ Meta , ❖ Super , and ✦ Hyper keys. By combining the modifier keys, it is possible to make (50 keys × 5 shift types) × 24 bucky keys = 4000 different inputs. This allowed the user to type very complicated mathematical text, and also to have thousands of single-character commands at their disposal. Many users were willing to memorise the command meanings of so many characters if it reduced typing time. This attitude shaped the interface of Emacs; [6] compare the use of the ⎋ Esc key in vi, due to the convenient position of the key on the ADM-3A terminal. [7] Other users, however, thought that so many keys were excessive and objected to this design on the grounds that such a keyboard can be difficult to operate. [5] Emacs uses "M-" as the prefix for ⎇ Alt when describing key presses: the "M-" stood for Meta on the space-cadet keyboard, and when Emacs was ported to PCs, the Alt key was used in place of Meta.
This keyboard included a Macro key which had limited application support. It also included four Roman Numeral keys (I, II, III, and IV) which allowed for easy interaction with lists of four or fewer choices. [5]
A keyset or chorded keyboard is a computer input device that allows the user to enter characters or commands formed by pressing several keys together, like playing a "chord" on a piano. The large number of combinations available from a small number of keys allows text or commands to be entered with one hand, leaving the other hand free. A secondary advantage is that it can be built into a device that is too small to contain a normal-sized keyboard.
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.
QWERTY is a keyboard layout for Latin-script alphabets. The name comes from the order of the first six keys on the top letter row of the keyboard: QWERTY. The QWERTY design is based on a layout included in the Sholes and Glidden typewriter sold via E. Remington and Sons from 1874. QWERTY became popular with the success of the Remington No. 2 of 1878 and remains in ubiquitous use.
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. They are commonly used in defined sequences of keys with another keys to trigger a specific action. These sequences are called keyboard shortcuts.
In computing, a Control keyCtrl is a modifier key which, when pressed in conjunction with another key, performs a special operation. Similarly to the Shift key, the Control key rarely performs any function when pressed by itself. The Control key is located on or near the bottom left side of most keyboards, with many featuring an additional one at the bottom right.
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.
In computing, a keyboard shortcut is a software-based assignment of an action to one or more keys on a computer keyboard. Most operating systems and applications come with a default set of keyboard shortcuts, some of which may be modified by the user in the settings.
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.
The Meta key is a modifier key on certain keyboards. It first appeared on the Stanford Artificial Intelligence Lab (SAIL) keyboard in 1970.
In user interface design, a mode is a distinct setting within a computer program or any physical machine interface, in which the same user input will produce perceived results different from those that it would in other settings. Modal interface components include the Caps lock and Insert keys on the standard computer keyboard, both of which typically put the user's typing into a different mode after being pressed, then return it to the regular mode after being re-pressed.
There are two major English language computer keyboard layouts, the United States layout and the United Kingdom layout defined in BS 4822. Both are QWERTY layouts. Users in the United States do not frequently need to make use of the £ (pound) and € (euro) currency symbols, which are common needs in the United Kingdom and Ireland, although the $ symbol is also provided as standard on UK and Irish keyboards. In other countries which predominantly use English as a common working language, such as Australia, Canada, and New Zealand, the US keyboard is commonly used.
The Fn key, short form for function, is a modifier key on many keyboards, especially external keyboards, and is not available for mobile devices. For use in a compact layout, combine keys which are normally kept separate. It-Alt + FN is typically found on laptops due to their keyboard size restrictions. It is also found on many full-sized "multimedia" keyboards as the F-Lock key. It is mainly for the purpose of changing display or audio settings quickly, such as brightness, contrast, or volume, and is held down in conjunction with the Caps Lock to change the settings.
The Gold key is a computer keyboard key used as a prefix to invoke a variety of single-key editing and formatting functions. Usually located in the top-left position of the numeric keypad on platforms such as the VT100, it is the signature element of a consistent user interface implemented by Digital Equipment Corporation (DEC) across multiple product lines.
Key rollover is the ability of a computer keyboard to correctly handle several simultaneous keystrokes. A keyboard with n-key rollover (NKRO) can correctly detect input from each key on the keyboard at the same time, regardless of how many other keys are also being pressed. Keyboards that lack full rollover will register an incorrect keystroke when certain combinations of keys are pressed simultaneously. Rollover has applications for stenotype, electronic music keyboards, gaming, and touch-typing generally.
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.
Super key (❖) is an alternative 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.
The Knight keyboard, designed by Tom Knight, was used with the MIT-AI lab's bitmapped display system. It was a precursor to the space-cadet keyboard and the later Symbolics keyboard.
A computer keyboard is a peripheral input device modeled after the typewriter keyboard which uses an arrangement of buttons or keys to act as mechanical levers or electronic switches. Replacing early punched cards and paper tape technology, interaction via teleprinter-style keyboards have been the main input method for computers since the 1970s, supplemented by the computer mouse since the 1980s.
Emacs, originally named 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 GNU Emacs, directly descended from the original, is ongoing; its latest version is 29.4 , released June 2024.
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.
This article is based in part on the Jargon File, which is in the public domain.