Architecture defines the practices, techniques and types of representations used by software architects to record a software architecture. Architecture is largely a modeling activity (Software architectural model). Architecture models can take various forms, including text, informal drawings, diagrams or other formalisms (modeling language). An architecture will often employ several different model kinds to effectively address a variety of audiences, the stakeholders (such as end users, system owners, software developers, system engineers, program managers) and a variety of architectural concerns (such as functionality, safety, delivery, reliability, scalability).

The ability to clearly and concisely describe (and document) the architecture for a solution is a key skill for architects, since the Architecture Description forms the “common language” by which the technical team gains a consistent understanding of the system to be delivered; additionally the Architecture Description is the starting point for other views and perspectives which may need to be created to communicate to other (non-technical) stakeholders. Another important role of the AD is to quickly and consistently bring new members of the technical team up-to-speed with the architecture of the system; as such the AD must be maintained during the SDLC to ensure it reflects the current state of the architecture for the system.