It's hard to imagine that just 20 years ago, most homes didn't have a personal computer. Now, it's harder to find a home that doesn't have one or more computers. With a computer, you can access the Internet, send and receive e-mail, chat with your friends, play games, share photos and videos, manage your personal finances, and do a lot of other fun and productive activities.
If you want to buy a computer you dont need to know how it works. But first of all, you should know about hardware and software.
Hardware refers to () the actual (, ) machine and its parts. Software is a list of instructions stored on media ( ) such as diskettes or CD-ROMs, or stored in the computers memory. Without some kind of software, hardware is useless. A computer without any programs would simply do nothing.
A computer has several main parts. If we compare a computer to a human body, the CPU (Central Processing Unit) is like a brain. It does most of the 'thinking' and tells the rest of the computer how to work. The CPU is on the motherboard, which is like the skeleton. It provides the basis for the other parts, and carries the nerves that connect them to each other and the CPU. The motherboard is connected to a power supply, which provides electricity to the computer. The various drives (CD drive, floppy drive, and on many newer computers, flash drive) act like eyes, ears, and fingers, and allow the computer to read different types of storage ( ), in the same way that a human can read different types of books. The hard drive is like a human's memory. Most computers have a sound card or another method of making sound, which is like vocal cords ( ). Connected to the sound card are speakers, which are like a mouth. Computers might also have a graphics card, which helps the computer to create visual effects.
One of the most important jobs that computers do for people is helping with communication. Computers have helped people move forward in science, medicine, business, and education. They also let other people communicate with each other, do their jobs almost anywhere, learn about almost anything, or share their opinions with each other. The Internet is the thing that lets people communicate between their computers.
Blogs are used by many people to say what they want on the Internet. Some people spend most of their time reading and writing blogs. Many people write about things that happen to them. Experts can use them to help people learn more. Some blogs are used by companies to sell things.
