Our sun is a star, and nine worlds (天体) move round it. Worlds like these are planets. But here are other stars, other suns, not only thousands of them, but millions of them. Do different stars have planets? We can see the planets round our own sun. But we haven't been anymore. The stars are too far away from us. Stars give out light, but the planets don't have any light of their own. So we can't see them. They are too far, and too dark. Still, we can tell that some stars have planets. While a big planet goes round, it pulls its star to one side. And sometimes we can see this. Then we know that the star has a planet. For example, Barnard's Star is a small red star. And it is the quickest star in the universe. But sometimes it moves slower, and then quicker again. We have known Bernard''s Star for many years, and now we are sure it has a planet.

    Life in the future will be different from life today. Between then and now many changes will happen. But what will the changes be?

    The population is growing fast. There will be many people in the world and most of them will live longer than people live now.

    Computers will be much smaller and more useful, and there will be at least one in every room. And computer studies will be one of the most important subjects in schools then. People will work fewer hours than they do now and they will have more free time for sports, watching TV and travels. Travelling will be much cheaper and easier. And many more people will go to other countries for holidays.

    There will be changes in our food too. More land will be used for building new towns and houses for all the people. Then there will be less room for cows and sheep, so meat will be more expensive. Maybe no one will eat it every day. Instead they will eat more fruit and vegetables. Maybe people will be healthier. Work in the future will be different too. Robots will do dangerous and hard work. Because of this, many people will not have enough work to do. This will be a problem.

    An atlas is-a book of maps. Atlases are made with different kinds of information about different parts and areas of a country or the world. They are prepared for desk use or travel use.

    Desk atlases are made for different groups of people with different needs. For example, students may use desk atlases to help learn Geography, and other people may use desk atlases to study a place. A popular type of the latest atlas shows the recent fact of the world. New atlases are often carefully produced to help people learn about the changes, such as name changes, boundary(界) changes and other important new information. A desk atlas can also have some different maps of the same place. For example, an atlas may include maps showing population and important products of a place.

    Travel atlases usually show the information about both natural and man-made features(特点). So it is not surprising to find universities, airports, forests, rivers, roads as well as cities, towns and villages in them. A travel atlas is often the first thing people need when they want to start a trip in a strange place.

    It often has a map of a whole country, and a map with more special information of each important place in the country. Take the atlas of the United States as an example, it often has a map of the whole country and then a map of each of the fifty states.

    A travel atlas may also point out the beautiful natural places. In the USA, the atlas may include national parks such as the Yellowstone National Park and some others to show the beauty of nature and interesting places to tourists.

    Mobile Apps are part of our daily life. Here are some of the most popular Apps.