Software Documentation is an important part of software engineering that isoften overlooked. Types of documentation include: * Architecture - Architectural overview of software; including relations to an environment, construction principles to be used in design and technical documentation, etc. * Design - The design of software components.* Technical - Documentation of code, algorithms, interfaces, APIs.* End User - Manuals for the end-user.* Operator - Manuals for the systems administrator.
From : en.wikipedia.org/wiki/Software_Documentation