Facebook is an Internet-based social network site that lets people get in touch with family and friends and reach out to people with common interests around the world, all through computer. It is very popular, with more than 900 million users. If Facebook were a country, it would have about three times the population of the United States.

    Documents filed with US. financial regulators say Facebook has hundreds of millions of active users who send billions of messages each day and upload 250 million photographs on their personal pages. Facebook users have registered 100 billion “friends.”

    On Facebook, “Friending” someone means you add the person to your list of people you can communicate with directly, which often allows the person to see more information about you than you share with the general public.

    Facebook was started by Mark Zuckerberg and other students at Harvard University in 2004, and has grown at an amazingly fast pace.

    Facebook makes money when advertisers pay to get access to hundreds of millions of Facebook users. Advertisers can often direct their messages to the people most interested in their products because Facebook computers keep track of information that users place on their pages. For example, a person interested in diving, planning a wedding, looking for work, or suffering from diabetes(糖尿病) may see advertisements related to those topics.

    Facebook has become so much a part of the culture of the United States and other nations that it has been the subject of a Hollywood movie. It is a key marketing tool for many businesses, and its users' content has been used as evidence in some divorce or criminal cases.

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    Alibaba opened China's version of Amazon's cashier-less store, “Tao Cafe” at its second annual Taobao Maker Festival taking place from 8—12 July, and then showed it to the public. By scanning a QR code（二维码）on Taobao app at the entrance of the store« consumers are tracked with cameras for facial recognition. After going through the checkout doors, customers will automatically make a purchase through their smartphones without needing to head to a register and be able to leave the store with what they buy in hand.

    The company, putting its efforts in Artificial Intelligence and data technologies, caused some ripples（波动）among offline retailers （零售商）. But if you think the e-commerce giant plans to get a slice of the physical-store pie, then you might get it wrong: “It's not about Alibaba wanting to open more cafes, we are not in the restaurant business.” it's about digitalizing the footprints of the visitors to an offline store, '' said Chris Tung, chief marketing officer of Alibaba Group.

    He said, for example, in the online world, Alibaba can always personalize every web page based on users interest and preference thanks to big data, “When you open our app, every moment is different.” But on the other hand, “offline is becoming not so exciting anymore”, because many physical stores are always found to be very similar with no variation.

    Tung said offline retailers could improve by adopting online data competence to link the identity of the customers» and optimize（优化）their in-store shopping experience. So in this sense, after physical stores have an understanding of what their customers need online, then they can allocate the products in the physical offline store accordingly. He further explained the pop-up Tao Cafe is one of the ways to present this “new retail” idea and opens up people's thinking and calls for more partnership.

    Rescue officials in Poland are working quickly to clear one of the country's highways. The roadway is covered with a sticky brown material. It is blocking cars from both directions.

    What is causing the mess? Milk chocolate. The problems began early Wednesday, after a huge truck carrying many tons of liquid chocolate overturned. Chocolate spilled out. It spread across six driveways of Poland's A2 highway.

    The liquid chocolate solidified（凝固）as it cooled, causing even more difficulties. The accident happened near the western Polish town of Slupca. Bogdan Kowalski is with the fire fighters of Slupca. He told the Associated Press that “the cooling chocolate is worse than snow”.

    Videos published on social media showed rescuers and cleaners were trying to move the sticky brown mess with a bulldozer（推土机）.

    The private Polish broadcaster TVN24 reported that the driver of the truck was taken to a hospital with a broken arm. The accident happened in the morning when there was little traffic. Nobody else was harmed.

    The sticky situation became a hot topic on social media. Some people offered to help the clean-up workers by eating the chocolate themselves.

    Marlene Kukawa is a media officer for Slupea police. She told the New York Times that rescue workers needed to remove the truck from the highway first. “The cleanup”, she said at the time, “will take a few hours or more.” She added that accidents are rare in this part of the A2 highway. And, she told the New York Times, she is sure the area has never experienced something quite like a huge chocolate spill.

    Congratulations on having been offered, and accepting, a place to study at Cambridge! This page offers some tips that will hopefully make your arrival at Cambridge as stress-free as possible.

    Before you arrive

    Your College or Department will send you all the information you need to prepare yourself for your time in Cambridge, including College information, for example, accommodation, course information, and similar related details. You will be sent an email asking you to complete the University's Student Registration exercise. It will only take a few minutes.

    Pre-arrival Freshers' Events this summer

    Around the world in August and September, Cambridge Alumni（毕业生）Groups will be hosting pre-arrival Freshers' Events for new students coming to Cambridge this autumn. These events are a great opportunity to prepare for university and make some friends before you arrive. There will be the chance to meet current students and alumni from whom you can get tips and advice for living and studying in Cambridge.

    Arrival and registration

    Most courses start in October. The term between October and December is known as Michaelmas Term in Cambridge. Officially, the first day of the Michaelmas Term is 1 October and this date will be shown on your offer letter. Your College or your Department will advise you about when to arrive. Ceremony activities begin around 1 October for most students. When you arrive in Cambridge, you should go first to your College. They will be glad to know that you have arrived safely and will advise you on what to do next.

    Matriculation

    Matriculation marks the formal admission of a student to membership of the University, and a College may not normally allow an unmatriculatied student to be a resident member of the College. Every freshman for matriculation must agree with the following belief by signing the Matriculation Registration Form:

    I promise to observe the Statutes and Ordinances of the University as far as they concern me, and to pay due respect and obedience to the Chancellor and other officers of the University.

    Trees are useful to man in three very important ways: they provide him wood and other products; they give him shade; and they help to prevent drought (干旱) and floods.

    Unfortunately, in many parts of the world, man has not realized that the third of these services is the most important. In his eagerness to draw quick profit from the trees, he has cut them down in large numbers.

    Two thousand years ago, a rich and powerful country cut down its trees to build warships, with which to gain itself an empire. It gained the empire but, without its trees, its soil became bare and poor. When the empire fell to pieces, the country found itself faced by floods and starvation.

    Even where a government realizes the importance of a plentiful supply of trees, it is difficult sometimes to make the people realize this. They cut down the trees but are too careless to plant and look after new trees. So unless the government has a good system of control, or can educate the people, the forests slowly disappear.

    This does not only mean that there will be fewer trees. The results are even more serious: for where there are trees, their roots break the soil up, allowing the rain to sink in, and also bind the soil. This prevents the soil from being washed away. But where there are no trees, the rainfalls on hard ground and flows away on the surface, and this causes floods and the rain carries away the rich top soil in which crops grow. When all the top soil is gone, nothing remains but worthless desert.

    You know those nutrition guidelines the government issues every few years? It turns out that following them isn't just good for your health. It's good for the planet, too.

    " What we found is that impacts vary across nations, but in the high­impact nations, in general, you can see that, if you follow a nationally recommended diet, despite the fact that these diets don't mention explicitly—or most of them don't explicitly mention—environmental impacts, that you are going to have lower environmental impacts due to that. So that's sort of fairly clear across all the high­income nations." said Paul Behrens, an environmental scientist at Leiden University in the Netherlands.

    The food we eat takes a big toll on the environment. A third of the ice­free land on Earth is used for agriculture, and according to some estimates, producing food accounts for roughly a fifth of all human­caused greenhouse gas emissions. Fertilizer runoff also leads to other problems, like the algae blooms in Lake Eerie and the Dead Zone in the Gulf of Mexico.

    However, following dietary guidelines would reduce those impacts, especially in wealthy countries like the US. "Most of the reductions come from meat and dairy," which have an outsized impact on land use and pollution, and are a major source of greenhouse gases.(That's partly due to cow farts. Seriously.) Following the suggestions would also mean eating fewer calories, since many people here eat more than they need.

    Overall, in high­income countries, Behren's team estimates that following the rules could result in as much as a 17 percent reduction in land use, a 21 percent reduction in nutrient pollution, and a 25 percent drop in agricultural greenhouse gas emissions. Cutting down on how much food we waste—which is roughly a third in the US—could help even more. The results are in the Proceedings of the National Academy of Sciences.

    Of course, people are notoriously bad at following diets. But: "These nationally recommended guidelines do actually have a knock­on effect on other areas of policy making. So if I'm developing a new healthy­eating­for­schools program then that's going to be based off a lot of detail that I get from the nationally recommended guidelines. So while it might not necessarily be the case that people follow directly …they actually are quite influential on the preparation of other advice."

    It seems that a smaller environmental footprint and a healthier lifestyle could go hand in hand.