Long ago the stage belonged to the United States and when people thought of tall American buildings the Sears Tower in New York City was mentioned. Other countries started developing their commerce industry and the quest to build a taller building was moved across oceans and now the tallest building in the world is located in Taipei, Taiwan. It's called the Taipei 101 and its topper antenna helps it reach 1,670 ½ feet high.
Tall buildings are marks of achievement not only for the people who design them but for the cities they tower over. There are radio towers that reach the 2,000 feet tall mark but if most of the space is not used for commercial use then it's not considered a building but a structure.
There is some debate about how a building is deemed a structural marvel, if it's built below sea level or if parts are not attached it cannot be considered a skyscraper. Oil platforms have been omitted since their structure is mainly below sea level and the only visible part is above water. Currently a building in Burj, Dubai is being named the tallest building in the world, it stands at an incredible height of 2,684 feet.
Occupancy is key when deciding whether a building meets the requirements for the worlds tallest. Height is a factor and Dubai has the current record, the United States is second with a radio tower that stands 2,063 feet high. The third belongs to China at 2,001 feet high. Many of the current skyscrapers are topped out and cannot extend any more height. This leaves engineers to design buildings that will house offices as well as sightseeing opportunities.
The battle for height is not limited to buildings. Clock towers, dams and churches can also be recognized. The manner in which they were built also has to do with how they rank on the tallest buildings scale. A brick and mortar building would not be in the same category as a lighthouse or radar tower. They must have form as much as function to be considered for the prestigious list of world's tallest building.
Each year brings a new challenge to those who want to top the list; even though there are buildings that are shorter than the current tallest one they still have more cultural significance. Examples would the Empire State Building, the Sears Tower and the Eiffel Tower in Paris, France. The Eiffel Tower held the record until 1931 and then was preceded by the Empire State Building in New York City. The World Trade Center towers took that record in 1976, they were destroyed in 2001. The CN Tower in Toronto, Canada held the record until 2008 when it was surpassed by the Shanghai World Financial Center in Shanghai, China.