Your interviewer will likely ask you knowledge-based questions to understand how well you are able to explain concepts to others. Be prepared for questions like this one by practicing a few possibilities ahead of time. In this case, injection molding is a process that involves heating and pressurizing a plastic material until it is molten, and injecting it into a steel mold with a cavity in the shape of the desired part. There are two sides to the mold, and a common issue is that parts get stuck when the mold is separating. Draft describes the practice of adding an angle or taper to the walls of the mold so that the part is less likely to get stuck. For example, the body of a plastic BIC lighter is more narrow at the top of the lighter and wider at the bottom, which allows it to be made at high volumes via the injection molding process.