I have a group of coders who are currently working on development of a large web based application. I would like my group of programmers to document the application they are coding in such a way that in addition to commenting their code, they produce a document that would be of asssistance to other coders in the fututre that will be working on modifying and customizing the application. In a sense, a document that will be used to navigate the code base of the application.
Is there any methodologies that could be followed to produce such a document? If I were to list out requrirements for the document, what should I specify?