A "line of business" is a particular product line. The term is also applied in EA to any functional area, including human capital, financial management, or logistics. A "line of business" is often the basis of an architecture inside the enterprise, and corresponds to the terminology "segment" used in Burk's levels. Another term of similar use if "domain" as in "domain architecture". A "line of business" may be a mission area or profit center, or it may be a support function or cost center. In EA the idea is to give priority to those areas that are important to the mission or produce profit.
In enterprise architecture the "line of business" or segment or domain is the level at which most business process reengineering, value chain analysis, supply chain analysis, operational analysis etc. occurs. An example of this is the Federal Segment Architecture Methodology. Another example is the Business Transformation Architecture (BTA) effort at DoD.
