Architecture is the art of planning, designing, and constructing buildings.
e.g. He studied classical architecture and design in Rome.
The architecture of a building is the style in which it is designed and constructed.
e.g. ...modern architecture.
e.g. ...a fine example of Moroccan architecture.
The architecture of something is its structure.
e.g. ...the crumbling intellectual architecture of modern society.
e.g. ...the architecture of muscle fibres.