Building
A building, or edifice, is a structure with a roof and walls standing more or less permanently in one place, such as a house or factory. Buildings come in a variety of sizes, shapes, and functions, and have been adapted throughout history for a wide number of factors, from building materials available, to weather conditions, land prices, ground conditions, specific uses, and aesthetic reasons. To better understand the term building compare the list of nonbuilding structures.
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.
Theory
A theory is a contemplative and rational type of abstract or generalizing thinking, or the results of such thinking. Depending on the context, the results might, for example, include generalized explanations of how nature works. The word has its roots in ancient Greek, but in modern use it has taken on several related meanings.
Building
Terrorist attacks can shake the foundations of our biggest buildings, but they cannot touch the foundation of America. These acts shattered steel, but they cannot dent the steel of American resolve.
George W. Bush in his "Address to the Nation" (September 11, 2001)
Design
People think it's this veneer — that the designers are handed this box and told, 'Make it look good!' That's not what we think design is. It's not just what it looks like and feels like. Design is how it works.
Steve Jobs (2003), as quoted in Rob Walker, "The Guts of a New Machine", The New York Times Magazine, 30 November 2003
Design
I think so many of the objects we're surrounded by seem trivial. And I think that's because they're either trying to make a statement or trying to be overtly different. What we were trying to do was have a very honest approach and an exploration of materials and surface treatment. So much of what we try to do is get to a point where the solution seems inevitable: you know, you think 'of course it's that way, why would it be any other way?' It looks so obvious, but that sense of inevitability in the solution is really hard to achieve.
Jonathan Ive (2003), Designer of the iMac, iBook and iPod, in iconeye 004 (July/August 2003)