1. Input Devices
The foremost task of a computer is to accept data. An input device is used to accomplish this task. An input device is used to enter the data and instructions into the computer. Advancement in the computer technology has resulted in a variety of input devices being available in the market. Keyboard and mouse are the most commonly used input devices.
Keyboard: Keyboard is the most popular input device that allows users to type alphabets, numbers, and operators, and also to control the cursor on the screen.
Mouse: Mouse is a pointing device that allows user to point to a specific position on the screen. It has two or three buttons on top for selecting/executing different operations. Pressing buttons of mouse is known as clicking of mouse. The mouse is placed on flat surface and moved around to move its controlling arrow on screen.
The arrow showing the position of mouse on screen is known as mouse pointer. Left button of mouse is used execute the operation associated with it. Right button/Middle buttons are associated with special operations in different situations.
Some of the other Input Devices are enlisted below:
Joy Stick It is a device used to control cursor on screen. Normally it is used in Games and specially designed simulation software.
Light Pen It is a device used for drawing pictures and for directly controlling screen operations.
Microphone It is a device used to accept audio inputs from the user.
Scanner It is a device used to capture digital images of printed documents, graphics or other printed media.
Touch Screens It is a display device, which is touch-sensitive and allows user to interact with the computer system by touching an area on the screen.
Bar Code Reader It is used to accept bar code inputs.A bar code is a series of vertical bars representing numbers and alphabets printed on product labels. One must have noticed all standard items like perfumes, greeting cards, books, cassettes available in the market have similar lines as shown in the figure,
known as bar codes. These can be read with the help of bar code readers.
Web Camera It is an easy to connect low-resolution digital camera normally employed for transfer of images on the web -based conferencing.
Digital Camera It is a high-resolution camera,which captures images and stores them in digital format. It has provision to connect to the computer using special computer communication cables (such as USB cables).