Architecture
Architecture is both the process and the product of planning, designing, and constructing buildings or any other structures. Architectural works, in the material form of buildings, are often perceived as cultural symbols and as works of art. Historical civilizations are often identified with their surviving architectural achievements.
Design
Design is the creation of a plan or convention for the construction of an object, system or measurable human interaction (as in architectural blueprints, engineering drawings, business processes, circuit diagrams, and sewing patterns). Design has different connotations in different fields (see design disciplines below). In some cases, the direct construction of an object (as in pottery, engineering, management, coding, and graphic design) is also considered to use design thinking.
Interior Architecture
Interior Architecture is the design of a space inside any building or shelter type home that can be fixed. It can also be the initial design and plan for use, then later redesign to accommodate a changed purpose, or a significantly revised design for adaptive reuse of the building shell. The latter is often part of sustainable architecture practices, conserving resources through "recycling" a structure by adaptive redesign. Generally referred to as the spatial art of environmental design, form and practice, interior architecture is the process through which the interiors of buildings are designed, concerned with all aspects of the human uses of structural spaces. Put simply, Interior Architecture is the design of an interior in architectural terms.
Design
Good design is also an act of communication between the designer and the user, except that all the communication has to come about by the appearance of the device itself. The device must explain itself.
Donald Norman (2002), The Design of Everyday Things, Introduction to the 2002 Edition
Architecture
Behold, ye builders, demigods who made England's Walhalla [Westminster Abbey].
Theodore Watts-Dunton, The Silent Voices, No. 4, The Minster Spirits.
Design
Disguise and complication are hindrances, both to good construction and good design, and as complication and disguise are expensive and wasteful... the interests of good art and true economy run on parallel lines.
Ernest Flagg, Small Houses: Their Economic Design and Construction (1922)