What is the difference between a mold and a cast?

A mold is used when you pour liquid material that hardens to a certain shape. Plastics parts for example are molded. Hot plastic is injected into a mold then cooled thus creating the finished part. The mold is designed in the shape of what you want the finished piece to look like. A cast is created in layers or liquid is poured into a mold to make a cast such as an animal foot.