Cloud computing means processing data and programs over the Internet instead of the hard drive of one’s computer. It involves computing over a network, where a program or application may run on many connected computers at the same time.

For some, cloud computing is a metaphor (比喻) for the Internet. It typically uses connected hardware machines called servers. Individual users can use the server’s processing power to perform any computing tasks, such as running an application or storing data. Thus, instead of using a personal computer every time to run the application, the individual can now run the application from anywhere in the world.

For businesses, cloud computing is an ideal way to reduce costs. With cloud services, a company doesn’t have to install applications on every single computer in the company. Instead, workers can log into a cloud with all the programs needed for their job. Everything would run on remote machines and local computers would just need to connect to those machines.

While cloud computing could change the entire computer industry, there are still some concerns about the safety of the data stored on the remote machines. It is true that it promises to offload many tasks. However, this technology raises a fundamental question. Is it safe to store one’s data on someone else’s computer? The cloud service provider needs to establish clear and related policies that describe how the data of each cloud user will be processed. Cloud service users should also be able to encrypt (加密处理) data that is processed or stored within the cloud to prevent unauthorized(未经授权的) access.

The Space Engineering Program in China dates back to the 1970s. More and more teenagers become interested in it. Below are some great achievements during the process of China’s space exploration (探索).

China’s first man-made satellite Dongfanghong 1 made China the ____________ country to send a satellite independently. Tiangong Program made it possible for scientists to ____________ so that more astronauts can live and do research in space. _____________ landed on the moon’s dark side. Pictures and videos sent back by China’s first Mars probe allowed us to see this ____________ planet at such a close distance. Thanks to the achievements above, China is now one of the leading countries in space exploration.

Don’t be too surprised if you see a car going down the road without a driver in Beijing these days. It might be one of Baidu’s self-driving cars. Last month, Baidu tested its self-driving cars on open roads in Beijing. Self-driving cars have been in progress since 2010, when Google said it was making such cars. From then on, companies like Tesla, Uber and Baidu tried to make and test their own self-driving cars.

Now, many people really want to buy a self-driving car if they have enough money. They think it will make their life easier. However, every coin has two sides.

Normally, when there is an obstacle (障碍物) in front of the self-diving car, the car will stop. But sometimes it also makes mistakes. In one test, when researchers sent a point of light in front of a moving self-driving car, the car stopped. And in another test, when researchers did it again, the car moved to another road. If scientists don’t solve the problem, some people may use the mistake to do bad things.

So self-driving at least now is still not safe enough. When we use our computers or smartphones, they sometimes don’t work well without any reason. If this happens to a self-driving car the results might be dangerous. So scientists are making improvements to work out the problem.