It’s a question we hear all the time. Even though most people use the words interchangeably, they’re not the same thing. Here’s the difference:
Cement is a binding agent that dries and hardens on its own. Examples have been found dating all the way back to Mesopotamia. Today, the most commonly used type for construction is Portland Cement, which was developed in the 1700’s. It’s a superheated mix of limestone and clay that hardens when it comes in contact with water, which is ideal because the cement stays strong in wet conditions – even underwater.
Concrete is a mixture of cement and other additives like sand, gravel or stone, which are known as the aggregate. The cement acts like a paste and binds the aggregate together. Again, the binding properties of the cement are activated through contact with water. In the end, the cement only makes up about 10-15% of the concrete mixture. Different chemicals can also be added to change the drying time or other properties of the concrete. Essentially, cement is like the flour in a concrete cake.
From the Pantheon to the Hoover Dam, concrete is responsible for some of the world’s most famous structures. Today, it’s the most widely used building material in the world.
Fun fact: Concrete comes from the latin word “Concretus,” which means “compact or condensed.”