Form & CompositionRevised
Structure
The internal organization holding one object's or composition's own parts together.
In practice
Structure is the internal organization that holds one object's or composition's parts together, often invisible from the surface. In a book, it is the sequence of chapters and headings and the page grid; in a chair, the frame that carries weight to the floor. When structure is clear, parts can be added or changed without the whole falling apart, which is why designers often settle structure before surface.
Often confused with System
Structure organizes the parts within one object or composition; a system applies one shared rule across many distinct components of a larger whole.
Try this
Take a magazine page and draw only its hidden structure: columns, margins and where text lines sit.