Architectural designs are built atop an initial idea, which may have a rough sketch that illustrates it. The idea may be further defined by a text list of items that a client wants to see in the design. For a house, this list might indicate the rooms and other features of the house, e.g. "three kids bedrooms, and a dining room with north-facing windows."
The tools used to create designs are often computer aided design (CAD) programs. CAD programs display several different views of an architectural design: front, left, right, back, top, bottom. An architect will typically start drawing in the top view, which is also called the plan view. In this view, he'll draw the top view of objects that comprise the design. For a house design, he'll include a drawing of a long rectangle with an oval in the center--the bathroom's bathtub. He'll also draw many straight-line segments in between the rooms and surrounding the house. These segments represent walls.
A benefit of creating designs with computer-based tools is the ease with which a virtual three-dimensional (3-D) model can be built from the 2-D design. Such models allow the architect and her client to walk through the proposed structure to evaluate it. Building 3-D models with traditional tools requires a great deal more time and, thus, money.
An architectural design will display a host of numbers that represent measurements. Every component of the design will have its size dimensions listed close to it, along with arrows that precisely indicate the image portion that the size number is referring to. For example, the front view of a Roman triumphal arch will display a two-sided arrow alongside the arch. The arrow will extend from the arch's base to its top and have a space at its midpoint. Inside the space will be the size of the arch's height. The architect will write this number in the units needed by the crew who'll build the arch. If the crew is based in England, those units will be meters and centimeters. If it's in the U.S., the units will be feet and inches.
"Architectural style" means what the term "flavor" means in ice cream: it's the combined effect and appearance of specific parts of a design. These parts may include the materials that will go into the physical structure that the design represents, the shape and size of parts of the structures or any other aspect of the structure and its design. Some example of the huge number of existing architectural styles clarify this term's meaning: the Gothic style of architecture refers to buildings, especially French cathedrals, built from 1150 to 1300 that have these features: pointed arches with four-part rib vaults (i.e., high, curved ceilings) and stained glass windows.
A more recent architectural style is the Cape Cod style, which applies to houses built in the first half of the 20th century. Cape Cod-style houses are found mostly in the northeastern U.S., and have roofs with steep slopes, left-right symmetry, wood construction and other features that distinguish it from other housing styles.