10. COMPUTER KEYBOARD, MOUSE & SPECIAL KEYS

COMPUTER KEYBOARD

•The keyboard is the most commonly used input device.

  The computer keyboard looks like a typewriter keyboard having numbers and

  letters.

•However, most computer keyboards, apart from having all the features of a

  typewriter keyboard also have extra keys such as the function keys, numeric  

  keys and the cursor or arrow or locate keys.

• The keys include:

•Special keys

•Alphabet keys (a-z)

•Numeric keys (0-9)

•Cursor keys or Arrow keys or locate keys

•Function keys.

THE MOUSE

•The mouse is a small box with one or more buttons that control the position of a pointer (called a cursor).

• In operation, the mouse is simply moved around on a table or desktop to guide the cursor to correct location is got, the user can then give instruction to the computer by pressing the button on the mouse.  Mouse has software and unless this facility has been installed in a computer, it cannot be used.  Mouse is communication between a computer system and its user more comfortable.

 

SPECIAL KEYS

•Space bar: This is the longest key on the keyboard. It is used for creating space between one word and the other.

•Enter or return key: It is used to instruct or command the computer to start execution.  In word processing, it is used to start new lines when creating texts.

•Delete key: The delete key is used to correct or erase wrong words or letters by putting the cursor under the words or letters to be deleted.

•Backspace key: This key is used for editing or correcting mistakes to the left of the cursor.

•Shift key: Some keys have two functions they can perform.  So to get the second function, the shift key must be held down while striking the   key in question.  Each alphabet key can produce small or capital letters.  To get the capital letter, or the upper case letter, the shift key must be held down while pressing the alphabet key of interest.

•Caps lock: This is used to lock all small letters so as to get the capital or the upper case letters.  When pressed again, all capital letters are locked; hence it is called caps lock.

•The alphabet keys: The alphabet keys are used in creating words or text.  The point the alphabet to be typed is usually located where the cursor is.

•The numeric keys: The numeric keys are used in entering numbers 0-9.  The numeric keys are usually located off to one side of the basic typewriter keys.  They look very much like the keys on a pocket calculator, and also perform the same function which is to input numbers for the computer to calculate with.

•The cursor control or arrow keys: The blinking highlighted mark (-) block, which always appears on the screen of the monitor, is called the cursor.  The cursor marks ones position where any character such as alphabets, number etc typed on the keyboard will appear on the screen.  The cursor can move up, down, right, and left on the screen using the arrow keys.

•The arrow keys can be seen with up, down, right, and left on the screen using the arrow keys.

  UP ARROW KEY – Moves the cursor up one line.

  DOWN ARROW KEY – Moves the cursor down one line. 

   LEFT ARROW – Moves the cursor to the left.

  RIGHT ARROW – Moves the cursor to the right.

The cursor or locate keys are also used to select a choice from the menu or list of option.

•The Function Keys: Modern computers have function keys on the keyboard, which are used to do some special things in a program or software. Standard keyboard has function keys from F1 to F10; while Enhanced keyboard has function keys F1 to F12.