- Alphanumeric keyboard
Alphanumeric keyboards include
typewriters and computerkeyboards. An alphanumeric keyboard is a device with many keys (usually marked with the letters of the alphabet, the numerical digits, and various extra keys.)
punch cardsand paper tape, interactionvia teletype-style keyboards became the main input devicefor computers. During the 1980s and 1990s almost all computers came equipped with them as the main form of interaction, and most users are familiar with using them.
There are different types of keyboard technologies.
The most popular layout of keys on the
modern-dayEnglish keyboard is called the QWERTYdesign, based on the most popular typewriterkeyboard layout. This has been further extended to the standard 104-key PC keyboard layout, with the addition of cursor keys, a calculator-style numerickeypad, two groups of special function keys, a key for the Windows Start menu(on IBMand clones), and other modifier keys. Some computer manufacturers have added keys specifically related to the Internetand
typists (as of 2007) use a stenograph, a kind of chorded keyboardused by most court reportersand closed caption reporters.
Despite the development of alternative input devices such as the mouse, touch sensitive
screens, pendevices, character recognition, voice recognition, and improvements in computer speedand memorysize, the keyboard remains the most commonly used and most versatile deviceused for direct human inputinto computers.
Stenotype Key punch
British and American keyboards
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