Although the terms cement and concrete often are used interchangeably, cement is actually an ingredient of concrete. Concrete is basically a mixture of aggregates and paste. The aggregates are sand and gravel or crushed stone; the paste is water and Portland cement. Concrete gets stronger as it gets older. Portland cement is not a brand name, but the generic term for the type of cement used in virtually all concrete, just as stainless is a type of steel and sterling a type of silver. Cement comprises from 10 to 15 percent of the concrete mix, by volume. Through a process called hydration, the cement and water harden and bind the aggregates into a rocklike mass. This hardening process continues for years meaning that concrete gets stronger as it gets older.
Cement: A fine powder made by combining limestone and other minerals, which then becomes the “glue” in making concrete.
Concrete: Made by combining cement, water, sand and gravel.
Asphalt: Asphalt pavement is approximately 95% aggregates, and 5% asphalt cement as a binder. The binder is a product of oil refining that acts to “glue” the aggregates together.