Use of in put devices

 These are some of the uses of input devices:
Keyboard
The Keyboard is the standard data input and operator control device for a computer.It consists of the standard QWERTY layout with a numeric keypad and additional function keys for control purposes.
Mouse 
The Mouse is a popular input device. You move it across the desk and its movement is shown on the screen by a marker known as a 'cursor'. You will need to click the buttons at the top of the mouse to select an option. 
Joystick
The joystick is a rotary lever. Similar to an aircraft's control stick, it enables you to move within the screen's environment, and is widely used in the computer games industry. 
The Optical Mark Reader (OMR) 

The Optical Mark Reader (OMR) can read information in the form of numbers or letters and put it into the computer. The marks have to be precisely located as in multiple choice test papers.
Light Pen
A Light Pen is a pointing device shaped like a pen and is connected to a VDU.
The tip of the light pen contains a light-sensitive element which, when placed against the screen, detects the light from the screen enabling the computer to identify the location of the pen on the screen.Light pens have the advantage of 'drawing' directly onto the screen, but this can become uncomfortable, and they are not as accurate as digitizing tablets. 
Sound Capture
With the addition of a sound card in one of the expansion slots of your computer you can "record" voice or music. The sound card digitizes the information into a form that the computer can understand.
Video Capture
With a video capture board in one of your computer's expansion slots you can capture video (photographic) images through a video camera.
The video capture board digitizes the image.