Key difference: Cement is a binder, a substance that is used to bind together materials. A binder is a substance that sets and hardens independently. Concrete is a combination of a cement and aggregate, a strong building material that endures for ages despite environmental effects.

Cement is a binder, a substance that is used to bind together materials. It dates back to the Romans, who used concrete made from crushed rock and burnt lime as a binder. A binder is a substance that sets and hardens independently.

There are two main types of concrete: hydraulic and non-hydraulic. Hydraulic cements are cements that harden due to hydration and chemical reactions that are not depended on precise water content in the cement. These types of cement, such as Portland cement, are used in wet conditions or even underwater. This is the most commonly used cement. Non-hydraulic cements are depended on water content in the cement, and must be kept at precise conditions in order to dry and strengthen. Hence, many contractors prefer not to use this cement.

Cement is mainly used in the production of mortar and concrete. Concrete is a combination of a cement and aggregate. An aggregate is coarse gravel or crushed rocks, usually limestone, or granite, mixed with sand. As a mixture of cement and aggregate, concrete is a strong building material that endures for ages despite environmental effects. Concrete is mixed with water in order to make it moldable and be able to be poured into a structure. Various chemical admixtures may also be added in order to achieve varied properties. After shaping, the concrete goes through a chemical process called hydration and solidifies and hardens into a rock-hard stone material. Concrete has a high compressive strength, long service life, high thermal mass, and a very low permeability, but it has a much lower tensile strength. Hence it is often reinforced with materials that are strong in tension, such as steel, or iron. Concrete can be damaged by a number of processes, such as force or freezing of trapped water.

Concrete is commonly used to for making architectural structures, foundations, walls: brick or block, bridges, roads, expressways, overpasses, runways, parking lots, dams, pools, reservoirs, pipes, etc. Famous structures such as the Roman Pantheon, the Hoover Dam, the Panama Canal, The Berlin Wall, etc. have been made with concrete.

Concrete stands the test of time and makes for cheap and affordable housing. However, it has some negative environmental impact. Concrete is a major contributor to greenhouse gas emissions. Still, to counteract this, it has become increasingly common to recycle the concrete from old buildings which have reached the end of their life.

The terms cement and concrete are often used synonymously; however, one should note that cement is an ingredient of concrete. Hence, there are no cement sidewalk, or cement mixers, there are concrete sidewalk and concrete mixers.

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