Steel is an alloy made up of iron and other elements such as carbon, manganese, chromium, and nickel. Steel is a strong metal used in many constructions.

Steel has existed for thousands of years. The first steel was created by the Egyptians when they mixed iron with a small amount of carbon. They would then heat the mixture until it turned into steel. Steel was used to make weapons and tools for the Egyptians.

Today, steel is mainly used in construction works such as buildings and bridges. The first skyscraper was built of steel in 1884-1885 in Chicago, Illinois.