Good documentation is crucial for success. Users and developers need to quickly understand how systems work.
We have written myriad documentation, including a manual for programmers using PEAR DB and a set of step-by-step instructions as part of a MySQL tutorial for administrators / users. Proper commenting inside source code and documentation blocks (which can be rendered by tools such as phpDocumentor) go a long way. Presentations are also part of our repertoire.
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