3.7 KEYBOARD

 It is the most common input device used for input of data and information into the computer system. In a keyboard alphabets are printed on the keys. The first keyboard was developed in 1800 century and was named as QWERTY keyboard. The standard layout of letters, numbers, and punctuation is known as a QWERTY keyboard, because the first six keys on the top row of letters spell QWERTY.

In general a computer keyboard has following key:

1. Alphanumeric Keys: It includes letters and numbers.

2. Punctuation Keys: These include comma, period, semicolon etc.

3. Special Keys: These can be, function keys, control keys, arrow keys and Caps Lock keys etc.


 All the modern keyboards of computer are classified as:

(a) Original PC keyboard having 84 keys,

(b) Advance Technology (AT) Keyboard having 101-104 keys, and

(c) Multimedia Keyboard having 120 – 140 keys.

 

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