The Internet is becoming important in our life. How much do you know about it?

What is the Internet?

The Internet is a large, world-wide collection (聚集) of computer networks( 网络). A network is a small group of computers put together. The Internet is many different kinds of networks from all over the world. These networks are called the Internet. If you have learned to use the Internet, you can have a lot of interest on the World Wide Web(网)

What is the World Wide Web?

The World Wide Web has been the most popular development of the Internet. The Web is like a big electronic (电子) book with millions of pages. These pages are called homepages. You can find information about almost anything in the world on these pages. For example, you can use the Internet instead of a library to find information for your homework. You can also find information about your favourite sport or film star, talk to your friends or even do some shopping on the pages. Most pages have words, pictures and even sound or music.

What is e-mail?

Electronic mail (e-mail) is a way of sending messages to other people. It' s much quicker and cheaper than sending a letter. If you want to use e-mail, you must have an e-mail address. This address must have letters and dots (点) and an" @ " (means "at"). For example: Lily @ Yahoo, com. Write a message, type a person's e-mail address, then send the message across the Internet. People don't need to use stamps, envelopes  or go to the post office since the invention of the Internet . Quick, easy and interesting — that' s the Internet .

    Robots are playing an important role in our life. They help us a lot.

    In factories, robots can help people do lots of work. They work faster and do not need a rest. People will feel bored if they do the same job again and again, but robots will not. And they can work in same dangerous places. Usually people cannot.

    In our homes, robots are useful, too. They can help us do some cooking. They can help blind people read newspapers and help the old people move some heavy things. They are our best friends. They are clean and do not need to eat food.

    However, robots are not as clever as people. They cannot think like us. If we do not "'teach" them how to do things first, they can do nothing.

    As space science develops, man has learned more and more about space. Space is not only amazing but also dangerous. While working in space, spacemen are facing danger.

    Scientists have found out that radiation(辐射) is the greatest danger to spacemen in space. When spacemen are working in space, they are in danger of radiation from the sun and other stars, which is bad for their health. Some special medicine may work a little, but there's no really helpful medicine.

    Space junk is also thought a great danger to spacemen. It's reported that there are 9,000 man-made things flying in space. About 30% of these are man-made satellites(卫星),10% are spaceships, and the rest are space junk. An explosion(爆炸) in 1996 made a cloud of 300,000 fragments(碎片), each at least 4 mm in size, and even a small piece of these knocked against a spaceship window and did some damage. Scientists are working on helpful ways to do with space junk.

    Although space is really dangerous, it interests everyone on the earth. In the near future, it may become usual for people to spend a few days in a space hotel. We may even choose to leave the earth and live in space for a few years. So we should care for space and do something to help improve the space environment.

    Many people like to travel by plane, but I don't like it because an airport is usually far from the city. You have to get there early and wait for hours for the plane to take off and it is often late. You can't open the window. You can't choose the food. Planes are fast, but it still takes hours to get out of the airport and into the city.

    I like traveling by train. I think trains are safe. Railway stations are usually in cities. When you are late for a train, you can catch another one. You can walk around in the train and open the windows. You can see many interesting things on your way. I know it takes a little more time.

    I also like cars. You can start your journey when you want to, and you don't need to get to a railway station or a bus stop. Also you can take many things with you in a car. But sometimes there are too many cars on the road.

    This is a street crossing. There are red and green lights at each corner. Drivers must watch the lights carefully.

    When there is a green light, the cars may go on. When there is a red light, the cars must stop.

    They must wait until the red light changes (变成)to green. Then they can go on. Sometimes the cars want to make a right turn or a left turn. They can make a right turn when the light is green or red. But they must wait until the green light is shining (闪亮) if they want to turn left. Some people are color-blind (色盲的). They can't see the difference (不同点) between red and green. These people mustn't drive, or there may be an accident (事故) .We must keep our street safe (安全的).