Casting involves pouring liquid metal into a mold which contain a hollow cavity of the desired shape, and then allowing it to cool and solidify. The solidified part is also known as a casting, which is ejected or broken out of the mold to complete the process. Casting is most often used for making complex shapes that would be difficult or uneconomical to make by other method.

The casting process is divided into two main categories: expendable and non-expendable. It is further broken down by the mold material, such as sand or metal, and pouring method, such as gravity, vacuum, or low pressure.

Expendable mold casting includes sand, plastic, shell, plaster, and investment (lost-wax technique) moldings Non-expendable mold casting includes Permanent Mold casting and Die Casting.