Interacting with Computers

If you think of the CPU as a computer’s brain, then you might think of the input devices as its sensory organs—the eyes, ears, and fingers. From the user’s point of view, input devices are just as important as the CPU, perhaps even more important. After you buy and set up the computer, you may take the CPU for granted because you interact directly with input devices and only indirectly with the CPU. But your ability to use input devices is critical to your overall success with the whole system. An input device does exactly what its name suggests: it enables you to enter information and commands into the computer. The most commonly used input devices are the keyboard and the mouse. If you buy a new personal computer today, it will include a keyboard and mouse unless you specify otherwise. Other types of input devices arc available as well, such as variations of the mouse and specialized "alternative" input devices such as microphones and scanners. This chapter introduces you to the keyboard and the mouse. You will learn the importance of these devices, the way the computer accepts input from them, and the many tasks they enable you to perform on your PC.