I often resort to placeholder assets when putting together prototype projects. Unity’s built-in selection of primitive shapes like the Cube, Quad, Sphere and Capsule are very useful toward that purpose. More often that not, any other assets you work with will be created externally and then imported into Unity. This is especially true with something as complex as a 3D mesh. However, there are reasons to create and/or edit meshes programmatically, and this lesson will serve as a helpful introduction.