While the U.S. is still debating about getting rid of the penny, Sweden is rapidly moving towards abolishing currency altogether. Though this may sound radical(过激的), it is a natural evolution in this digital society.

    Sweden, which was the first European country to introduce banknotes in 1661, has just been working harder to convince its residents that digital payments are a safer alternative to carrying cash.

    Over the years, the idea has gained popularity with residents, especially the younger generation that is much more comfortable with technology. Today many banks don't even have ATMs and some have stopped handling cash altogether!

    Tickets to ride public buses in most Swedish cities can only be purchased via cell phones. Numerous businesses are also moving towards accepting only digital payments. Even the homeless that sell street paper to make ends meet have to start accepting this mode of payment!

    But despite its growing popularity, some people don't like this radical idea. They include the homeless, elderly people as well as those living in rural areas who are still uncomfortable with mobile phones and computers. But the officials are confident that in the very near future, they will be able to convince everyone to move this safe and more cost-effective payment system.

    Sweden is not the only country trying to abolish paper currency and coins. The movement is rapidly gaining ground in Denmark and Finland as well. In 2014, Israel announced a three-step plan to go cashless and just last week the vendors(小贩)of a popular street in Sydney declared they would stop accepting currency from customers. Whether this phenomenon spreads remains to be seen. But one thing is for sure—With increasingly advanced payment systems being introduced every day, pulling out cash is rapidly becoming “uncool”.

    US student Vanessa Tahay stands out from the other teenagers in her school. Her skin is dark, her accent is thick, and if you ask her, she will tell you these are the things she is proudest of. Tahay is a poet, and at 18 she was considered among the best in Los Angeles.

    When she is on the stage, audiences often go silent. They also laugh, shout and cry. But this doesn't come easily for someone who comes from a village that sits at the base of a huge mountain range in Central America. When she first appeared at school, she was teased by others for being short and different. She never spoke, so they called her “mouse”.

    “How do I defend myself?” Tahay thought. “I don't know how.”

    “Keep going,” her mother would tell her. “At some point, you'll learn.”

    She spent hours after school and on weekends watching the same DVDs: English without Barriers.

    Tahay's elder brother, Elmer, persuaded her to go to the after-school poetry club. In the last six years, her English teacher Laurie Kurnick has turned Cleveland Charter High School's poetry program into one of the most respected in the city. Her team draws from the likes of D.H. Laurence, Pat Mora and Kendrick Lamar to create poems about their own lives. The poems focus on many things —some funny, some painful.

    The first time Tahay read the group's poems, chills went up her spine (脊柱). “I wish I could write like that,” she thought. “I want to say something.”

She wrote her first poem about her first year in America. She called it Invisible. The day her turn came to recite in front of the team, she broke down crying. She cried for 15 minutes. “I had so much held in,” Tahay said. “I couldn't even finish it.”

    But she kept at it despite her less-than-perfect grammar, spelling and diction (措辞). Still, she wouldn't tell her friends about her poetry because she worried they would make fun of her.

    But with time, her poems changed her. “They gave me pride,” Tahay said. “They told me that I'm worth something.”

    “She had this innocence,” Kurnick said. “This willingness to be genuine and show you things you don't ever see.”

    Who is smarter? A human being or artificial intelligence?

The question swept the world last week when a Google-developed program called AlphaGo defeated the world top player, South Korean Lee Se-dol, 4-1.

    So, what comes next?

    Some people have been arguing that artificial intelligence, or AI in short, will be a bad thing for humans. In an interview with the BBC in 2014, UK scientist Stephen Hawking warned that “The development of full artificial intelligence could mean the end of the human race.”

    So are we really about to live in the world shown in the Terminator movies?

    “Not quite,” answered The Economist. After all, it's not hard to get a computer program to remember and produce facts. What is hard is getting computers to use their knowledge in everyday situations.

    “We think that, for the human being, things like sight and balance(视觉平衡), are natural and ordinary in our life.” Thomas Edison, founder of Motion Figures, a company that is bringing AI to boys, told the newspaper. “But for a robot, to walk up and down just like human beings requires various decisions to be made every second, and it's really difficult to do.”

    As The Economist put it, “We have a long way to go before AI can truly begin to be similar to the human brain, even though the technology can be great.”

    Meanwhile, John Mark off of The New York Times said that researchers should build artificial intelligence to make people more effective.

    “Our fate is in our own hands,” he wrote. “Since technology depends on the values of its creators, we can make human choices that use technology to improve the world.”

    Bill Gates and the president of General Motors have met for lunch, and Gates is going on and on about computer technology. "If automotive technology had kept pace with computer technology over the past few decades, you would now be driving a V-32 instead of a V-8, and it would have a top speed of 10, 000 miles per hour," says Gates. "Or, you could have an economy car that weighs 30 pounds and gets a thousand miles to a gallon of gas. In either case, the sticker price of a new car would be less than $50.Why haven't you guys kept up?"

    The president of GM smiles and says, "Because the federal government won't let us build cars that crash four times a day."

    Why is that funny (or not funny, as the case may be)? Human beings love to laugh, and the average adult laughs 17 times a day. Humans love to laugh so much that there are actually industries built around laughter. Jokes, sitcoms and comedians are all designed to get us laughing, because laughing feels good. For us it seems so natural, but the funny thing is that humans are one of the only species that laughs. Laughter is actually a complex response that involves many of the same skills used in solving problems.

    Laughter is a great thing—that's why we've all heard the saying, "Laughter is the best medicine." There is strong evidence that laughter can actually improve health and help fight disease. In this article, we'll look at laughter—what it is, what happens in our brains when we laugh, what makes us laugh and how it can make us healthier and happier. You'll also learn that there's a tremendous amount that no one understands yet.

    The term "smiling depression" —appearing happy to others while actually suffering depressive symptoms—has become increasingly popular. In fact, many people who experience a low mood and a loss of pleasure in activities manage to hide their condition in this way. And these people might be particularly easy to suicide.

    While smiling depression is not a technical term that psychologists use，it is certain to be depressed and manage to successfully mask the symptoms. The closest technical term for this condition is "atypical depression: It can be very hard to spot people suffering depression because they may seem like they don't have a reason to be sad — they have a job, an apartment and maybe even children or a partner. They smile when you greet them and can carry pleasant conversations. In short, they often put on a mask to the outside world while leading seemingly normal and active lives. Inside, however, they often feel hopeless and down, sometimes even having thoughts about ending it all.

    People with smiling depression put on a happy face to the outside world, but they can experience a lift in their mood as a result of positive occurrences in their lives. Other symptoms of this condition include overeating, feeling a sense of heaviness in the arms and legs and being easily hurt by criticism or rejection. They are also more likely to feel depressed in the evening and feel the need to sleep longer than usual. With other forms of depression, however, your mood might be worse in the morning and you might feel the need for less sleep than you are normally used to.

    So how can they break this circle? A starting point needs to be known that this condition actually exists and that it's serious. Only when we stop ignoring our problems because we think they're not serious enough can we start making an actual difference. Then we can find purpose by taking the attention away from ourselves and placing it onto something else. Feeling that our lives matter is finally what gives us purpose and meaning — and this can make a significant difference for our mental health and well-being.