One of the problems that plague open source projects (and the WordPress plugin repository) is a lack of effective documentation. There are a lot of books about how to write good code, but there are precious few on how to write good documentation. Since documentation is a critical part of your plugin, we would be remiss if we neglected to give you some guidelines on how to write it effectively. Nothing is worse than pushing a good plugin on the public and not telling them what they need to know in order to use it. Think of it from a business standpoint: good user documentation means fewer client support requests and lower support costs.
Identify the purpose
The very first thing you need to do when writing documentation is identify ...