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Hub AI
Dead key AI simulator
(@Dead key_simulator)
Hub AI
Dead key AI simulator
(@Dead key_simulator)
Dead key
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, in addition to the normal base letter keys.
For example, if a keyboard mapping (such as US international) has a dead key for the circumflex, ^, the character â can be generated by first pressing ^ and then a.
Usually, the diacritic itself can be generated as a free-standing character by pressing the dead key followed by space; so a caret (free-standing circumflex) can be typed by pressing ^ and then Space.
The dead key is mechanical in origin, and "dead" means without movement. On mechanical typebar typewriters, all characters are of equal width. As a key is pressed, a metal typebar strikes the character onto an inked ribbon, transferring ink to the paper, and a mechanism is triggered which causes the paper (inserted in a carriage) to move forward one space. To use a single diacritic, such as the acute accent, with multiple foundation characters (such as á, é, í, ó, ú), the decision was made to create a new character, the acute accent or diacritic ´, which did not exist in typesetting as of that date. Due to this design change in the mechanism, striking the key containing the accent did not advance the paper (the key was "dead" or non-spacing), meaning it could be followed by any character that was to appear under the acute accent, producing an overstruck character. This second key moved the paper carriage forward.
Note that with mechanical keyboards, the acute accent can be followed by any character to create new combinations, such as q with an acute accent.
A dead key is different from a typical modifier key (such as AltGr or ⌥ Option), in that rather than being pressed and held when another key is struck, the dead key is pressed and released before striking the key to be modified. In some computer systems, there is no indication to the user that a dead key has been struck, so the key appears dead (nothing immediately happens). But in some text-entry systems, the diacritic is displayed, along with an indication that the system is waiting for another keystroke to complete the typing sequence.
Computers, however, work differently. The dead key temporarily changes the mapping of the keyboard for the next keystroke, which activates a special keyboard mode rather than actually generating a modifier character. Instead of the normal letter, a precomposed variant, with the appropriate diacritic, is generated. Each combination of a diacritic and a base letter must be specified in the character set and must be supported by the computer font in use.
There is no precomposed character to combine the acute accent with the letter q, striking ´ and then q is likely to result in ´q, with the accent and letter as separate characters. However, in most systems, the invalid typing sequence may be discarded.
Dead key
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, in addition to the normal base letter keys.
For example, if a keyboard mapping (such as US international) has a dead key for the circumflex, ^, the character â can be generated by first pressing ^ and then a.
Usually, the diacritic itself can be generated as a free-standing character by pressing the dead key followed by space; so a caret (free-standing circumflex) can be typed by pressing ^ and then Space.
The dead key is mechanical in origin, and "dead" means without movement. On mechanical typebar typewriters, all characters are of equal width. As a key is pressed, a metal typebar strikes the character onto an inked ribbon, transferring ink to the paper, and a mechanism is triggered which causes the paper (inserted in a carriage) to move forward one space. To use a single diacritic, such as the acute accent, with multiple foundation characters (such as á, é, í, ó, ú), the decision was made to create a new character, the acute accent or diacritic ´, which did not exist in typesetting as of that date. Due to this design change in the mechanism, striking the key containing the accent did not advance the paper (the key was "dead" or non-spacing), meaning it could be followed by any character that was to appear under the acute accent, producing an overstruck character. This second key moved the paper carriage forward.
Note that with mechanical keyboards, the acute accent can be followed by any character to create new combinations, such as q with an acute accent.
A dead key is different from a typical modifier key (such as AltGr or ⌥ Option), in that rather than being pressed and held when another key is struck, the dead key is pressed and released before striking the key to be modified. In some computer systems, there is no indication to the user that a dead key has been struck, so the key appears dead (nothing immediately happens). But in some text-entry systems, the diacritic is displayed, along with an indication that the system is waiting for another keystroke to complete the typing sequence.
Computers, however, work differently. The dead key temporarily changes the mapping of the keyboard for the next keystroke, which activates a special keyboard mode rather than actually generating a modifier character. Instead of the normal letter, a precomposed variant, with the appropriate diacritic, is generated. Each combination of a diacritic and a base letter must be specified in the character set and must be supported by the computer font in use.
There is no precomposed character to combine the acute accent with the letter q, striking ´ and then q is likely to result in ´q, with the accent and letter as separate characters. However, in most systems, the invalid typing sequence may be discarded.