Many years ago, people relied on the sun, the moon and stars to find their way around. Later, the compass was introduced. And now, we have satnav（卫星导航）systems to guide us. A satnav system uses groups of satellites to show the user's location. They send information to a receiver, such as a smart phone, to show us where we are.

    The earliest built satnav system is the Global Positioning System, which belongs to the US. Then there is Russia's Global Navigation（导航）Satellite System, the European Union's Galileo and China's own satellite navigation system, BeiDou.

    On October 14, 2017, an ARJ21-700 plane, which was the first domestically-produced jet equipped with the BeiDou navigation system, successfully completed a test flight. The results showed the performance of the system developed by China matches that of similar systems produced abroad, according to the Commercial Aircraft Corporation of China.

    Since its introduction in 2000, the Beidou navigation system has seen increasing numbers of applications linked to everyday life, from shared bikes to farming.

    When it comes to shared bikes, smart locks that support BeiDou chips offer more accurate positioning than others, making it easier to find a bike.

    Farmers can use BeiDou-enabled tractors to plow（犁）the soil and use unmanned aircraft with BeiDou to sow seeds, which can improve efficiency and make better use of resources. BeiDou's farming applications have spread from Heilongjiang province to Beijing, Liaoning, Shanxi, Hubei and other regions across China.

    With its many uses, the Beidou navigation system is even playing a big role in the Belt and Road Initiative（— 带—路）. “To date, the BeiDou system has covered most parts of the Asia-Pacific region, as well as counties along the Silk Road Economic Belt and the 21^st Century Maritime Silk Road” said Yang Changfeng, Chief designer of the BeiDou system.

    Today, there are more than 20 BeiDou satellites above our heads, and China plans to launch even more this year to expand the BeiDou network to better serve the Belt and Road Initiative.

    “As BeiDou expands its overseas reach, it will be increasingly popular in the logistics （物流）industry,” said Miao Qianjun, secretary-general of the navigation services association. “Ships, for example, can use it to position themselves while sailing across oceans to European countries, no longer limited to Southeast Asian regions in the near future.”

    When we think of a generation gap we usually think of conflicting tastes in music, or pastimes. But now the generation gap is handwriting. After one teacher in Tennessee discovered that she had students who couldn't read the assignments she was writing on the board, she posted it on the Internet saying handwriting should be taught in schools.

    Opponents claim that handwriting has become out of time in our modern world. Typed words have become a primary form of communication. Once a practical kill handwriting is no longer used by the vast majority of Americans. It is no longer taught in schools, and some claim that the time that it would take to teach it could be put to better use, for instance, by teaching the technical skills.

    But even in today's world there are still plenty of reasons to pick up a pen and apply it to paper. Many American institutions still require original signatures, for instance, signing for a registered letter and buying a house. And original signatures are much more difficult to forge(伪造) than their digital counterparts. There is also strong evidence that writing by hand is good for the mind. It activates a different part of the brain, and improves fine moving skills in young children. People also tend to remember what they write by hand more than what they type, and the process of writing by hand has been shown to stimulate ideas. Besides, studies have shown that kids who write by hand learn to read and spell earlier than those who don't. Not to mention, handwriting is pleasing, as is evidenced by the fact that no one has ever typed a love letter. And handwriting remains popular as an art form.

    Yes, we live in a modern world, but we live in a modern world that is based on fundamental values.

    Audrey Hepburn won an Academy Award as Best Actress for her first major American movie，Roman Holiday，which was released in 1953．But she is remembered as much for her aid work as for her acting．

    Born in Belgium in 1929，Audrey's father was British and her mother was Dutch．Audrey was sent to live at a British school for part of her childhood．During World War II，she lived and studied in the Netherlands. Her mother thought it would be safe from German attacks．Audrey studied dance as a teenager and during college when she returned to London after the war．But she realized she wasn't going to be a ballerina （芭蕾舞女演员）．So she began taking acting parts in stage shows．Later she began to get small parts in movies．

    But it was Audrey Hepburn's move to America that brought her true fame．In 1951 she played the character"Gigi"in the Broadway play of the same name to great critical praise．Two years later，Roman Holiday made her a star at the age of 24．

    Audrey made more than 25movies．Among her most popular roles was Holly Golightly in Breakfast at Tifany's in 1961．Three years later she played Eliza Doolittle in My Fair Lady．

    She was married two times and had one son by each husband．In 1989，the UN Children's Fund named Audrey a goodwill ambassador．She travelled all over the world in support of UNICEF （联合国儿童基金会） projects．The UN agency said she was a tireless worker．She often gave 15interviews a day to gain money and support for UNICEF projects．

    Audrey Hepburn often said her loyalty to UNICEF was the result of her experiences as a child during World War II．She said she knew what it was like to be starving and to be saved by international aid．She was a goodwill ambassador until her death in 1993from colon cancer．

    In the future we might live somewhere other than Earth, like Mars. Some people ask how this will be possible. Well, Mars is in fact a lot the same as the earth. The days are almost the same as those on the earth. However, the two planets vary in temperature.

    Since there is mostly carbon dioxide on Mars, it would be quite difficult for a human to just land on it. So, special types of homes and space suits have to be designed. The space suits should be almost like the ones astronauts use now, and except that they have to be warmer so that the astronauts can survive the cold temperatures. The space suits must also be able to withstand (承受) high pressure and potentially dangerous radiation that can kill.

    The houses should be similar to our homes today with a slight difference. All of the houses and other buildings should be built inside a large dome (圆顶状物) or bubble. The domes should be made out of glass, and would also be able to prevent radiation from affecting the people inside. The domes will be connected to a machine (like plants which turn carbon dioxide into oxygen).

    With Mars' population growing, how would the people on its surface get fresh food and water? Just like humans use domes, they can also use domes to grow plants. However, the domes where the plants are grown must be built to expand. Once we upgrade the domes to a larger size then we can grow more food by cultivating (种植) more plants. To get the food or come in connect with other domes, there will be long narrow tunnels like roads that connect to each dome separating them by several doors so that the pressure in each dome can remain the same.

    On Mars, so many other things are available to us. As humans, we can have access to rare and fairly expensive metals that aren't very easy to get hold of on Earth, and a colony on Mars enhances (提高) our chances of finding these metals. So when someone here on Earth says that going to Mars is impossible, please tell them that they'll never know it until they try and they may try very soon. After all it's our future. Why not make it on Mars?

    Even for a first-time visitor to China, it is impossible to ignore the popularity of Quick-Response (QR) codes. These square-shaped black-and-white symbols in WeChat or Alipay where QR codes are scanned to add new friends or make payments.

    The QR Code system originated in Japan. The engineer Masahiro Hara felt the limitation of the one-dimension barcode in use and thus developed the QR codes which could carry data horizontally and vertically. QR codes could hold much more information than barcode due to their extra dimension. In addition, QR codes have larger data capacity, smaller print—out size and higher resistance to dirt and damage, which make them widely applied in many other applications.

    Though the technology of QR codes is complicated, we can easily create our own QR codes with the help of QR code generators, many of which are available online for free. Users could enter the data they wish the QR code to display, and the generator turns it into a symbol that can be printed or displayed in electronic form. The process of creating QR codes could be really fun when we customise the design of the codes according to our specific needs. For instance, we can adjust the color, add a logo, and create social options etc. Moreover, dynamic (动态的) QR codes are also available. They are more various than standard QR codes because they allow users to edit data entered previously whereas data in standard QR codes cannot be edited once printed. Plus, don't limit your QR code to one mobile scanner. Anyone can scan your code with any reader. A lower barrier to entry makes success more likely for you and the user.

    Meanwhile, we must also recognize the vulnerability of QR codes. Due to its easy access, criminals can steal simply by replacing the QR codes with their own, routing cash into their own bank accounts. Hence, we should all become more conscious towards virtual money transactions through QR codes and participate in additional security measures.

Coolest Bookstores in the World

    Where did you buy your last book? Chances are that you bought it on the Internet. But if you did, you missed the remarkable experience of browsing in a real bookstore. These days bookstores offer lots of great books and plenty more.

    Eslite Dunnan Store

    Time magazine once named Eslite Dunnan Store in Taiwan province, China "Asia's best bookstore". One visit to the store tells you why. The store, spread across five floors, offers a combination of restaurants, music and over 200,000 books. With its comfortable reading spots, visitors sometimes say it's like a library. Others have called it the "7-Eleven of bookstores" because it's open 24 hours a day.

    Book Garden

    The world's biggest bookstore is Tehran, Iran's Book Garden with 700,000 square feet of space. In addition to restaurants and a theater, the Book Garden features a park on the roof. Visitors can pick up one of 1,000 free books to read while enjoying the fresh air and sunshine from the Book Garden's rooftop park.

    Saraiva Bookstore

    Rio de Janeiro's Saraiva Bookstore might be the world's most colorful bookstore. The visible upper level is lined with books arranged by their colors. This rainbow effect provides a color welcoming for shoppers as they arrive. A rainbow path also leads young readers into the children's section.

    Liberia Acqua Alta

    Venice, Italy, is a city surrounded with water. Its books are displayed in all things related to water such as boats, bathtubs to protect them when the shop floods during high tide. It overlooks one of Venice's many canals, and the smell of old books fills the air.