From times of old, mans quest to reach for skies has been a success story. From the first test flight to space, the wright brothers story, its been a story that seemly has no end as advancement in different area keeps it going.

The word skyscraper originally refers to buildings of 10 to 20 stories, but by the late 20th century the term was used to describe high-rise buildings of unusual height, generally greater than 40 or 50 stories, normally a building is called a skyscraper if it clearly stands out above the surrounding built environment and significantly changes the city's overall skyline.
The crucial developments that allowed for the construction of modern skyscrapers were steel ,
glass , reinforced concrete, water pumps, and
elevators.
As the population density of urban areas has increased, so has the need for buildings that rise rather than spread.
The rapid growth in urban commerce in the United States in the 19th century augmented the need for city business space, and the installation of the first safe passenger elevator made practical the erection of buildings more than four or five stories tall. Although the earliest skyscrapers rested on extremely thick concrete walls at the ground level, architects soon turned to the use of a cast- iron and wrought-iron framework to support the weight of the upper floors, allowing for more floor space on the lower stories.
As steel is stronger and lighter in weight than iron, the use of a steel frame made possible the construction of truly tall buildings.
Some notable skyscrapers in existence ;

• PETRONAS TWIN TOWERS // KUALA LUMPUR, MALAYSIA
  
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• EMPIRE STATE BUILDING NEW YORK CITY
  
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• CHAOYANG PARK PLAZA,CHINA
  
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skyscraper records for the year 2017

Around the world in 2017, there are a staggering 144 new towers that reach above 200 meters (660 feet) tall.That includes an unprecedented 15 “supertall buildings,” defined as reaching at least 300 meters (980 feet) tall.
From Shenzhen and Jakarta to New York City, to even Pyongyang in North Korea, 69 cities have erected at least one skyscraper.
China, for the 10th straight year, tops the ranking, building more than half of the latest skyscrapers in 35 of its cities. Shenzhen alone has completed a dozen, followed by Nanning with seven high-rises, and Chengdu with five. Notably, many of these buildings have cropped up in smaller towns like Dalian, Dongguan, and Suzhou, which China has classified as “new first-tier cities,” in hopes of boosting investment and economic activity in their less populated areas.The country’s obsession with skyscrapers is a reflection of its rapid urbanization, as it undergoes what researchers say is the largest human migration in history. It’s also a result of China’s pivot toward modern architecture beginning in the early 2000s.
Africa is just beginning to move upwards. The latest and first skyscraper in Africa to make it onto CTBUH’s annual building review is the Britam Tower in Nairobi, Kenya. At slightly over 200 meters tall, the office tower is the tallest in the East African country and the second tallest in all of Africa. By CTBUH’s height criteria, it’s also the continent’s first skyscraper since 1973, when the Carleton Center, measuring 223 meters, in Johannesburg, South Africa, was completed.
Work has already begun on a 300-meter-tall hotel in Kenya that will unseat the Carleton Center. That project is expected to be completed in 2019. Morocco’s tallest skyscraper may come in the form of a 250-meter-tall multi-use building called the Al Noor Tower. Earlier this year, China’s state-owned railway construction corporation announced that it had won the bid to help build it.

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