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Keyboard
                 Keyboard is the standard input device. It is mainly used to type text and to send the instructions to a
                 computer with the help of keys. Keys are the buttons on the keyboard that represent alphabets, numerics,
                 alphanumerics and special characters. The keys can be used individually or in combination with other
                 keys. The standard keyboard contains 104 keys.


















                 Depending on the position or placement of the keys, the layout of a keyboard comes in various styles such
                 as QWERTY, QWERTZ, AZERTY and DVORAK. QWERTY keyboard is the most commonly used keyboard.
                 It is based on the English Language. Its name is derived from the sequence of the six alphabetical keys
                 positioned on the upper row of the keyboard. AZERTY type keyboard is mostly used in France (‘A’ and
                 ‘Z’ characters replace ‘Q’ and ‘W’ on such keyboards). QWERTZ type keyboard is widely used in Germany
                 and Central Europe.

                      Do you know?

                      In Laptop, Notebook and Tabs, keyboard is referred as ‘Keypad’. Christopher Latham Sholes was the
                      inventor of keyboard.



                 Mouse
                 Mouse is a hand-held device which is used on a flat surface and is represented
                 by a pointer on the screen. The pointer on the screen moves when the mouse is
                 moved by the user. A mouse generally consists of two buttons and a scroll wheel
                 on its top.

                 By pressing (clicking) the buttons of the mouse, the user gives instructions to the computer. The mouse
                 was invented by Douglas Engelbart.
                 The most commonly used mouse nowadays is the optical mouse. It has no moving parts and uses LED
                 (Light emitting diode) to detect the movement.


                                    Joystick

                                    Joystick is a pointing device whose function is similar to a mouse, except that a mouse
                                    pointer stops moving on the screen as soon as the user stops moving it, while the
                                    joystick pointer continues to move in the direction towards which the joystick has
                                    been pointed.

                                    To stop the pointer, the user has to bring the joystick to its upright position. It is
                                    generally used to play video games.


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