Concrete is the base substance of the North American construction industry, and it is particularly important to the tile and stone trades. It comes in many forms, a very few of which are:
Redi-mix, the stuff most driveways, concrete slabs, bridges and other structures are made of.
Mortars, to include thin set mortar. Generally, anything that contains portland cement and some sort of aggregate can be considered “concrete.”
For our purposes we’ll stick with the driveway material. :)