Materials and their properties are very important to know when constructing a building.  Ching explains the use of many materials, concrete is made of cement, water, and many mineral materials such as sand, gravel, etc. Concrete by itself is very good withstanding compression, but concrete is horrible against tension. Therefore concrete has to be reinforced with steel so that it can be resistant to tension, these steel bars inside the concrete can be as wide as 32 (mm) in diameter (1.26 inches). However, the more wide they are, the heavier they become, something to be aware of. Brick is another material used in construction. Brick is a rectangular prism made out of clay, sometimes mud to change the surface texture of the brick . Ching explains that there are two types of brick: Face brick is special clay to add color and other features to make it look “pretty”, common brick in the other hand is the opposite because it does no such thing.