Keyboard is a typewriter-like device, which contains keys to feed information into the computer. In general, keyboards are available in two models: The standard keyboard with 83-84 keys; and enhanced keyboard with 104 or more keys The keys of a standard computer keyboard along with their functions are described below:

• Typewriter Keys: These are normal keys on the keyboard. They include letters, numbers, and punctuation symbols. The typewriter keys are used for typing and designing. Quite often, the keys function as short-cuts to different commands.

• Function Keys: These keys, labelled F1 to F12, are located at the top end of the keyboard. The functions they perform depend on the software that is being used.

• Numeric Keys: The numeric keys are located just below the function keys. In numeric keys. the numerals are written at the bottom of each key and at the top are some special characters. Also, the right-hand side of the keyboard contains the numeric key pad, comprising calculator-like keys. Some of these keys have double functions. The switch-over between the two functions of a numeric key pad is controlled by the key marked NUM LOCK. For example, the key marked 7 works as a Home key only when the NUM LOCK key is OFF. When the NUM LOCK key is ON (indicated by the green light on top right of the keyboard). the keys marked 1. 2. 3. 4, 5, 6, 7, 8, 9. o function as Numeric keys. and on pressing anyone of them. a number gets displayed on the screen.

• Cursor Control Keys: These keys marked as are called the Left, Right. Up and Down Arrow keys, respectively. These keys enable you to move the cursor to the left, right. up or down the screen - one line or one character at a time.

• Caps Lock Key: Normally, an alphabet is typed in lower case. If you press the Caps Lock key once (i.e. when the LED status indicator, a green light on top right of key board. of Caps Lock is lit). any letter you type will appear in the uppercase (capital). This effect can be reversed simply by pressing the Caps Lock once again.

• Shift Key: Holding the Shift key down and then pressing a letter key creates an upper case letter. However. if the Caps Lock is ON, then this effect is reversed. Where there are two symbols or characters on a key, holding down of the Shift key causes the upper symbol to appear. The upper symbols are _ ! @ # $ % A & * ( ) _ + I : { } " : < > ? etc.

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• Ctrl and Ait Keys: The Ctrl (Control) and Alt (Alternate) keys are often used in combination with other keys to carry out special actions. For example, pressing Ctrl and C simultaneously aborts the current task or command from being executed in MS-DOS and returns to DOS prompt. By pressing Ctrl, Alt and Del (Delete) keys simultaneous!y, the machine automatically restarts.

• Enter Key: The Enter key is also referred to as the Return key. The Enter key is mainly used for two purposes. First, it alerts your PC that you have finished giving the instruction so that it can process or execute the instruction. Second, while using a Microsoft Word program, pressing the Enter key begins a new paragraph or a new line.

• Tab Key: The Tab key moves the cursor along a line to a preset point. It lets you indent paragraphs and line-up columns, text or numbers. In some softvvares, the Tab key helps you to move from one option to another in a menu.

• Esc (Escape) Key: In most applications, you can use the Esc key to cancel or to ignore the entry or command that you have just entered.

• Delete and Backspace Keys: Pressing Delete erases a space or character (one space/character at a time) that is placed to the right side of the blinking cursor. On the other hand, the Backspace key erases the character to the left side of the blinking cursor. It moves the cursor back, one character at a time-erasing what you typed last.

• Page Up and Page Down Keys: The Page Up and Page Down keys are used to move to the preceding and next pages of the document respectively.

• Home and End Keys: The Home and End keys takes the cursor to the top (beginning) and end of the document, line or window respectively.