Office buildings are usually loosely grouped into one of three categories: Class A, Class B, or Class C. These classifications are all relative and largely depend on context. Class A buildings are considered the best of the best in terms of construction and location. Class B properties might have high quality construction, but with a less desirable location. And Class C is basically everything else.
Central Business District (CBD)
Office buildings located in the central business district are in the heart of a city. In larger cities like Chicago or New York, and in some medium sized cities like Orlando or Jacksonville, these buildings would include highrises found in downtown areas.
Suburban office buildings
This classification of office space generally includes midrise structures of 80,000-400,000 square feet located outside of a city center. Cities will also often have suburban office parks which assemble several different midrise buildings into a campus-like setting.