is a cutaway photo of the AeroTech Initiator rocket. Note
it has several features not found in smaller hobby rockets.
thing is that as large and as complex as rockets get, they're
still just variations on this basic design. There are fundamental
physical principles which restrict what a stable and efficient
rocket will be like. Of course, details of design and selection
of materials differ widely, but most rockets really are "rocket
shaped" and made up of these basic pieces.