5b14a17c_for_Agile_Software_Development__2
[0] User documentation [1] Users, User Managers [3] .I typically base my usage guide and training materials on the use cases for the system -the use cases describe how the actors work with the system, therefore they should be a very good foundation on which to base both of these documents. .User documentation should be considered part of the user interface for your system and therefore should undergo usability testing. [4] Yes [2] 
Your users may require a reference manual, a usage guide, a support guide, and even training materials. It's important that you distinguish between these different types of documents because the way that each one is used varies: one is for quick lookups, one is for discovering about how to work with the system, one is for how to obtain additional help, and one is for training.
Agile/Lean Documentation: Strategies for Agile Software Development
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