How do tall buildings stay up? Each has a strong frame, like a skeleton. The frame is steel beams and columns.

Steel is very strong. The building pushes down on the columns. The columns are squeezed.

Under the building is a foundation. It goes down into the ground. It holds the building up.

Concrete is strong when it is squeezed. It is weak when it is pulled apart.

So people put steel bars inside concrete. Then it is strong when it is pulled.

Wind pushes on tall buildings. They sway a little.

Taipei 101 has a huge pendulum at the top. It weighs 660 tonnes. This is true as of November 2026.

Tall buildings need elevators. Elevators let people ride up. So builders could make buildings taller.

Elisha Otis showed a safe elevator. He stood on the platform. Then its rope was cut. The platform held.

The first skyscraper was in Chicago. It was the Home Insurance Building. It had 10 stories. It was 138 feet tall.

The Empire State Building has 102 stories. It opened in 1931. It was the tallest for about 40 years.

The Burj Khalifa has 163 floors. It is 828 meters tall. In November 2026 it is the tallest building in the world.

Words to know

• skeleton: body's frame
• concrete: hard gray stuff
• pendulum: swinging weight
• foundation: building's base