Dead Key - Dead Keys On Various Keyboard Layouts

Dead Keys On Various Keyboard Layouts

A key may function as a dead key by default, and many non-English keyboard layouts in particular have dead keys directly on the keyboard. The basic US keyboard does not have any dead keys, but the US-International keyboard layout, available on Windows and the X Window System, places some dead keys directly on similar-looking punctuation marks. Old computer systems, such as the MSX, often had a special key labeled dead key, which in combination with the Ctrl and Shift keys could be used to add some of the diacritics commonly needed in the Western European languages (´, `, ˆ and ¨) to vowels that were typed subsequently.

In the absence of a default dead key, even a normal printing key can temporarily be altered to function as a dead key by simultaneously holding down another modifier key (typically AltGr or Option). In Microsoft Word, using the Control key with a key that usually resembles the diacritic (e.g. ^ for a circumflex) acts as a dead key.

On the Macintosh, many keyboard layouts employ dead keys. In the U.S. layout, the following selection of dead keys appears:

• ⌥ Option+e → á, é, í, ó, ú
• ⌥ Option+` → à, è, ì, ò, ù
• ⌥ Option+u → ä, ë, ï, ö, ü, ÿ
• ⌥ Option+i → â, ê, î, ô, û
• ⌥ Option+n → ã, õ, ñ

For example, when ⌥ Option+E are first pressed simultaneously and then followed by A, the result is á. On a Macintosh, pressing one of these Option-key combinations creates the accent and highlights it, then the final character appears when the key for the base character is pressed. However, some diacritically-marked Latin letters less common in the Western European languages, such as ŵ (used in Welsh) or š (used in many Eastern European languages), cannot be typed with the U.S. layout, which predates Unicode and only provides access to characters found in the legacy Mac Roman character set. Access to many more diacritics is provided by the U.S. Extended keyboard layout.

In AmigaOS, dead keys are generated by pressing Alt in combination with F (acute), G (grave), H (circumflex), J (tilde) or K (trema) (e.g., the ALT-F combination followed by the a key generates á and ALT-F followed by e generates é, whereas ALT-G followed by a generates à and ALT-G followed by e generates è).