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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    Have you ever wondered why people drive on a different side of the road? It might seem bizarre that U. K. drivers stay on the left, but they're not the only ones. Around 35 percent of the world population do the same, including people in Ireland, Japan, and some Caribbean islands.

    Originally, almost everybody traveled on the left side of the road. However their way of transport was quite different from today: Think about four legs instead of four wheels. For Medieval swordsmen on horseback, it made sense to keep to the left to have their right arms closer to their enemies. Getting on or off was also easier from the left side of the horse, and safer done by the side of the road than in the center.

    So why did people stop traveling on the left? Things changed in the late 1700s when large wagons (货车) pulled by several pairs of horses were used to transport farm products in France and the United States. The wagon driver sat behind the left horse, with his right arm free to use his whip to keep the horses moving. Since he was sitting on the left position, he wanted other wagons to pass on his left, so he kept to the right side of the road.

    The British Government refused to give up their left-hand driving ways, and in 1773 introduced the General Highways Act, which encouraged driving on the left. This was later made law thanks to The Highway Act of 1835.

    When Henry Ford showed his Model T in 1908, the driver's seat was on the left, meaning that cars would have to drive on the right hand side of the road to allow front and back passengers to exit the car onto the roadside. However, British drivers remain on the left, and this is highly unlikely to change.

    A long-term American study shows the importance of early education for poor children. The study is known as the Abecedarian Project. It involved more than one-hundred young children from poor families in North Carolina.

    Half of the children attended an all-day program at a high-quality child-care center. The center offered educational, health and social programs. Children took part in games and activities to increase their thinking and language skills and social and emotional development. The program also included health foods for the children.

    The children attended the program from when they were a few weeks old until the age of five years. The other group of children did not attend the child-care center. After the age of five, both groups attended public school.

    Researchers compared the two groups of children. When they were babies, both groups had similar results in tests for mental and physical skills. However, from the age of eighteen months, the children in the educational child-care program did much better in tests.

    The researchers tested the children again when they were twelve and fifteen years old. The tests found that the children who had been in the child-care center continued to have higher average test results. These children did much better on tests of reading and mathematics.

    A few years ago, organizers of the Abecedarian Project tested the students again. At the time, each student was twenty-one years old. They were tested for thinking and educational ability, employment, parenting and social skills. The researchers found that the young adults who had the early education still did better in reading and mathematics tests. They were more than two times as likely to be attending college or to have completed college. In addition, the children who received early education were older on average, when their first child was born.

    The study offers more evidence that learning during the first months and years of life is important for all later development.

    The researchers of the Abecedarian Project believe their study shows a need for lawmakers to spend money on public early education. They believe these kinds of programs could reduce the number of children who do not complete school and are unemployed.

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    From Antigua to Zanzibar, these spots promise an incredible trip for 2019.

    Antigua, Guatemala

    "Antigua is worth every penny, but that doesn't mean you'll have to empty your wallet," says Hudson. There are plenty of budget-conscious activities. It won't cost you a coin to visit Santo Domingo del Cerro, an outdoor sculpture park. Wanting something sweet? Head to ChocoMuseo. Admission is free and so are the samples!

    Odessa, Ukraine

    Odessa is having a bit of a tourism boom nationwide-not that we're surprised, given its sandy beaches and pastel-colored buildings-but it's still fairly under the order for international audiences. You can also count on this port city for affordable fun. Tickets to the Odessa Opera House start at a mere $ 2!

    Bogotá, Colombia

    "Travelers on budget will find Colombia's vast capital, far more of a bargain and every bit as fascinating," says Hudson. "It's free to visit Museo de Oro and on Sundays many of the big roads are closed to accommodate food carts, street entertainers, and pedestrians."

    Zanzibar

    Zanzibar attracts vacationers with its white sand beaches, greenish-blue tides, colorful coral reefs, and oceanfront seaside. Of course, wandering in historic Stone Town is pretty appealing too. Either way, you needn't spend a penny in this amazing place. It's also worth noting that Jozani Forest is the only place in the world you can see endangered red colobus monkeys.

 German artist HA Schult is an unusual artist who uses trash(废物) to make sculptures. "We are living in the time of garbage," says Schult. "I created a thousand sculptures of garbage. They are a mirror of ourselves." Here, Schult was talking about his 1,000 trash sculptures in the form of humans. He first exhibited them in 1996 in the western German state of North Rhine-Westphalia.

"They are social sculptures," he explains. "They are not only sculptures for the eyes. They are sculptures to spread the idea that we live in the time of garbage." So far, Schult's social sculptures have been on show in Paris, in Moscow's Red Square, on the Great Wall of China, and in the desert next to the Pyramids of Giza near Cairo.

 HA Schult's work is unforgettable. Although his work has had a big influence on the art world, Schult remains modest about his creations. "Artists have to learn every time. We are not important. All that counts is the time in which we are living."

 Trash art has been around for years. But it seems that only the popular artists are regarded as true artists when working with trash. Why can't common people be considered artists when they use the same things and change them into some form of personal art? Maybe it's because we all have our own preset ideas of what art is and isn't, or whom artists are or should be.

 You can be an artist like Schult if you try. Look at used metal cans. What might be done with them? Imagine them in any number of new uses, or imagine them simply as an art form. What about boxes or clothing? Boxes can usually serve as new storage containers and houses for pets. And clothing? Imagine taking old clothes and turning them into hats or hanging organisers.