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 .

    How green are you ? Do you know how to be green?

    We all need a healthy environment, but we produce waste every day and it does harm to our environment. Though we are young, we can still do something to help. In fact, even the simplest everyday activities can make a real difference to the environment. Here are some ideas for you.

    Reduce

    Reduce means “use less”. Don't waste things. This saves money and reduces pollution and waste going into the environment. Before we buy something new, think whether it is really necessary—or maybe the old one will be just as good! When we do buy things, choose local products if possible, and try not to buy too many things from abroad.

    Reuse

    Reuse means “use again”. Use things for as long as possible. When we buy things, make sure that they last a long time. We should look after them so that they will last, and we should repair them if we can instead of throwing them away and buying new ones. Don't use a paper cup or a paper bag. It's better to use a china cup and a lunch box because you can use them again.

    Recycle

    Recycle means “change things into something else”. Though it takes energy(精力) to change something into something else, it's better than throwing things away or burning them. Find out what can be recycled in your neighborhood and take part in recycling programmes. We should also buy products made from recycled materials, such as recycled paper, to help save trees.

So please remember these three words： reduce, reuse and recycle.

    What is the first thing you want to do when you see someone yawn(打哈欠)? You want to yawn, too! Yawning is contagious.

    Scientists have found that all people yawn. Babies start to yawn even before they are born. The earliest yawn takes place when a baby is still inside its mother. When young children are about one year old, they start to yawn when they see others yawning. That's why scientists seem to think yawning is contagious.

    It's no secret that yawning is contagious, but why do we yawn? Well, scientists are not really sure.

    Some think we yawn because we feel bored. Recently scientists studied two groups of students between the ages of 17 and 19. One group watched music videos, and the other watched a boring color test. Scientists compared the numbers of their yawns and found that the color test group yawned more times than the video group.

    Another reason about yawning has to do with breathing. Some scientists believe that when we are bored or tired, we breathe more slowly. As our breathing slows down, we cannot get rid of(去除) enough carbon dioxide (CO₂) in our bodies. When there is too much carbon dioxide, our bodies will tell the brains (大脑) to breathe deeply. The result is a big yawn.                                                           

    In 2007, scientists suggested a new reason. They said that the reason people yawned was to cool down their brains. These scientists found that people who were warmer than others yawned more often.

    Scientists are still trying to find out why yawning happens and why it is so contagious. But they are only sure that when one person yawns, almost everyone else nearby wants to yawn, too.

    How do people find their ways? At first, people did it by looking at the sun, the moon and stars, Later, we started to use the compass(指南针).Today, there are navigation satellite systems.

    A navigation satellite system uses groups of satellites, they send information to a receiver, such as your smart phone. Then they can find where you are.

    The earliest navigation system is the Global (全球的) Positioning System(GPS) of the United States, The US has put 24 satellites into space to make sure GPS can locate a person correctly and globally. Russia's GLONASS and European Union's Galileo can also work globally.

    The BeiDou Navigation Satellite System (BDS) is China's homegrown navigation system. It was set up in 2000. With it, China became the third country to build a navigation system after the US and Russia.

    BeiDou can find you wherever you are. It helps you go faster by finding shortcuts and using correct directions. When you are in trouble and call the police, they will know exactly where you are if you have a smart phone that uses BeiDou.

    Today, there are more than 20 BeiDou satellites above our heads. And the system is able to offer open services to the Asia— Pacific area.

    China plans to send more BeiDou 3 satellites into space. BeiDou—3's position accuracy(精确度) is less than five meters, By 2020, the BeiDou system will have 35 satellites and  begin serving Globally.