Good documentation is crucial for success. Users and developers need to quickly understand how systems work.
We have written myriad documentation, including the DB package's section of the PEAR Manual, the Overloading page of PHP's Manual and a popular 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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