Class 2 Computer – Chapter1: Computer overview
Table of Contents
What is a machine:
Machines are made my human beings to make our work easier. A computer is also a machine which has found immense use by human beings in last few decades.
We use computers at many places like school, banks, hospitals etc. Computers are useful for entertainment like playing games and listening music. Computers also used for education as we can take online classes and practice many softwares like paint..
Computers use electricity to work and therefore they are also called electronic machine.
Types of Computers:
There are many different types of computers:
Desktop Computers:
A desktop computer is a personal computer that has a keyboard and monitor and sits on the desk. Desktop computers are bigger in size and have separate parts. The CPU Cabinet is shown below next to monitor. Latest desktop computers also have cpu cabinet parts embedded inside monitor body.
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Laptop Computers
Laptop computers are much smaller than desktop computers and they can be kept on our laps. The laptop computer is the most popular type of computer for use in work and school. They are portable due to their smaller size and also lightweight (1-2 kg), so they can be carried around more easily than a desktop computer.
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Tablet Computer
Tablet computer is smaller than laptop. Tablet computer is a mobile computer that can be used while sitting or standing. It includes a touchscreen or touch screen.
The tablet is an electronic device which functions as an electronic tablet, digital paper, and personal computer all in one. It looks like a pad of paper with an LCD screen on it. The user can write on the tablet by using his finger, stylus, or the mouse that is attached to it.
Some of the common uses of tablets are reading e-books and other written materials, checking email, playing games etc.
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All above computers are called personal computers.
What is booting
Computer booting is the process that starts your computer. Your PC or laptop boots when you turn it on or press a key.
Booting starts by checking all the hardware devices, such as keyboard and monitor, to see if they are ready to be used. The next step is loading the operating system from hard disk.