Compare the idea, physical, and computer models.

Idea is the foundation for everything. It is where the concepts were built to be encoded, materialized, rendered or modeled inside a computer. Computer models could be represented in three dimensional figure for further detailing and solid conceptualization. A physical model could be drawn out of the computer model or the idea model (either ways could be applied in different fields and situations). It is something that you can touch whether a miniature or a real sized one.

Some type of thing that was invisible

La olla es de metal por que se calienta mas rápido, y las manijas son de madera por que así no se calientas y tienden a estar mas frías.