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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    University Room Regulations

    Approved and Prohibited Items

    The following items are approved for use in residential rooms: electric blankets, hairdryers, personal computers, radios, televisions and DVD players. Items that are not allowed in student rooms include: candles, ceiling fans, fireworks, waterbeds, sunlamps and wireless routers. Please note that any prohibited items will be taken away by the Office of Residence Life.

    Access to Residential Rooms

    Students are provided with a combination(组合密码) for their room door locks upon check-in. Do not share your room door lock combination with anyone. The Office of Residence Life may change the door lock combination at any time at the expense of the resident if it is found that the student has shared the combination with others. The fee is $25 to change a room combination.

    Cooking Policy

    Students living in buildings that have kitchens are only permitted to cook in the kitchen. Students must clean up after cooking. This is not the responsibility of housekeeping staff. Kitchens that are not kept clean may be closed for use. With the exception of using a small microwave oven(微波炉) to heat food, students are not permitted to cook in their rooms.

    Pet Policy

    No pets except fish are permitted in student rooms. Students who are found with pets, whether visiting or owned by the student, will suffer an initial fine of $100 and a continuing fine of $50 a day per pet. Students receive a written notice when the fine goes into effect. If, one week from the date of written notice, the pet is not removed, the student is referred to the Student Court.

    To above prices, please add $3 for first book and $1 for each additional book for postage & handling. Foreign countries add $5 per book. Send orders to Quackwatch, P. O. Box 1747, Allen Avenue, NY 18105. The checks must be in US dollars. We cannot process credit card orders. Please use our order form from Amazon.com and include your email address.

    In a world with limited land, water and other natural resources (资源), the harm from the traditional business model is on the rise. Actually, the past decades has seen more and more forests disappearing and globe becoming increasingly warm. People now realize that this unhealthy situation must be changed, and that we must be able to develop in sustainable (可持续的) ways. That means growth with low carbon or development of sustainable products. In other words, we should keep the earth healthy while using its supply of natural resources.

    Today, sustainable development is a proper trend in many countries. According to a recent study, the global market for low-carbon energy will become three times bigger over the next decades. China, for example, has set its mind on leading that market, hoping to seize chances in the new round of the global energy revolution. It is now trying hard to make full use of wind and solar energy, and is spending a huge amount of money making electric cars and high-speed trains. In addition, we are also seeing great growth in the global markets for sustainable products such as palm oil (棕榈油), which is produced without cutting down valuable rainforest. In recent years the markets for sustainable products have grown by more than 50%.

    The major challenge of this century is to find ways to meet the needs of growing population within the limits of this single planet. That is no small task, but it offers abundant new chances for sustainable product industries.

    I admire my father for as long as I can remember. I loved the way he treated people with such respect and kindness.

    On Sundays we usually took the bus into Manhattan, where we would do interesting things, like riding the Circle Line. He would point out every landmark and tell us the history behind it. He loved to take us on the subway to Nathan's in Coney Island. Once there, he would give my sister and me each a five-dollar bill and then he would enjoy himself for the afternoon with his newspapers.

    In 1968, we went to see the movie “Oliver”, a Charles Dickens' classic story of a young orphan(孤儿) boy called Oliver. On the way home from the theater that afternoon he told us how he was raised in an orphanage(孤儿院) in New York after both of his parents died. He told us the nuns(修女) were wonderful to him and loved him like a mother would. As he grew older, he was placed in a few foster(寄养) families before he joined the Army.

    When we were teenagers, he still took us out each weekend and he would ask us to invite specific friends to join us and he would pay for them. We often went to Yankee Stadium to watch the baseball game and he bought us tickets in the least expensive seats. To keep the cost down, he waited for us in the car where he read his newspapers and then took a nap(小睡).

    He was always happy and appreciated everything he had. He loved his two little girls and later his two granddaughters. He gave so much, yet he had so little. He thought he was the richest man in the world.

    British children used to play conkers (板栗游戏) in the autumn when the horse-chestnut trees started to drop their shiny brown nuts. They would select a suitable chestnut, drill a hole in it and thread it onto a string, then swing their conker at that of an opponent until one of them broke. But the game has fallen out of favour. Children spend less time outdoors and rarely have access to chestnut trees. Besides, many schools have banned conkers games, worried that they might cause injuries or nut allergies.

    That sort of risk-averseness(规避风险) now spreads through every aspect of childhood. Playgrounds have all the excitement designed out of them to make them safe. Many governments, particularly in societies such as America, have tightened up their rules, requiring parents to supervise(监管) young children far more closely than in the past. Frank Furedi of the University of Kent, a critic on modern parenting, argues that allowing children to play unsupervised or leaving them at home alone is increasingly described as a symptom of irresponsible parenting.

    In part, such increased caution is a response to the huge wave of changes. Large-scale urbanization, smaller and more mobile families, the move of women into the labor market and the digitization of many aspects of life have unavoidably changed the way that people bring up their children. There is little chance that any of these trends will be changed, so today's more intensive(精细化 ) parenting style is likely to go on.

    Such parenting practices now embraced by wealthy parents in many parts of the rich world, particularly in America, go far beyond an adjustment to changes in external conditions. They mean a strong bid to ensure that the advantages enjoyed by the parents' generation are passed on to their children. Since success in life now turns mainly on education, such parents will do their best to provide their children with the schooling, the character training and the social skills that will secure access to the best universities and later the most attractive jobs.

    To some extent that has always been the case. But there are more such parents now, and they are competing with each other for what economists call positional goods. This competition starts even before the children are born. The wealthy classes will take their time to select a suitable spouse and get married, and will start a family only when they feel ready for it.

    Children from less advantaged backgrounds, by contrast, often appear before their parents are ready for them. In America 60% of births to single women under 30 are unplanned, and over 40% of children are born outside marriage. The result, certainly in America, has been to widen already massive social inequalities yet further.

    All the evidence suggests that children from poorer backgrounds are at a disadvantage almost as soon as they are born. By the age of five or six they are far less "school-ready" than their better-off peers, so any attempts to help them catch up have to start long before they get to school. America has had some success with various schemes involving regular home visits by nurses or social workers to low-income families with new babies. It also has long experience with programmes for young children from poor families that combine support for parents with good-quality child care. Such programmes do seem to make a difference. Without extra effort, children from low-income families in most countries are much less likely than their better-off peers to attend preschool education, even though they are more likely to benefit from it. And data from the OECD's PISA programme suggest that children need at least two years of preschool education to perform at their best when they are 15.

    So the most promising way to ensure greater equality may be to make early-years education and care for more widely available and more affordable, as it is in the Nordics. Some governments are already rethinking their educational priorities, shifting some of their spending to the early years.

    Most rich countries decided more than a century ago that free, compulsory education for all children was a worthwhile investment for society. There is now an argument for starting preschool education earlier, as some countries have already done. In the face of crushing new inequalities, a modern version of that approach is worth trying.