Definitions:
1)"The art or practice of designing and constructing buildings."
~Oxford dictionary (apple widget)
2) "Concept that focuses on the components or elements of a structure or system and unifies them into a coherent and functional whole, according to a particular approach in achieving the objective(s) under the given constraints or limitations. See also behavioral design."
~businessdictionary.com
3)"Architecture design refers to the actual design and layout of spaces."
~www.wisegeek.com/what-is-architecture-design.htm
