Following are the top 20 pages of the manual, sorted by the number of user notes contributed. These sections could use a polish, those notes represent 6.6% of the 25647 total user notes.
Notes | Page -------+--------------------------------------------------------- 114 | http://php.net/manual/en/function.curl-setopt.php 110 | http://php.net/manual/en/function.date.php 108 | http://php.net/manual/en/function.strtotime.php 95 | http://php.net/manual/en/function.session-start.php 89 | http://php.net/manual/en/function.array-search.php 86 | http://php.net/manual/en/function.array-merge.php 85 | http://php.net/manual/en/function.number-format.php 83 | http://php.net/manual/en/function.serialize.php 82 | http://php.net/manual/en/function.exec.php 82 | http://php.net/manual/en/function.mail.php 81 | http://php.net/manual/en/function.substr.php 80 | http://php.net/manual/en/features.http-auth.php 77 | http://php.net/manual/en/function.preg-replace.php 77 | http://php.net/manual/en/function.header.php 74 | http://php.net/manual/en/function.implode.php 74 | http://php.net/manual/en/function.utf8-encode.php 74 | http://php.net/manual/en/function.fsockopen.php 73 | http://php.net/manual/en/install.windows.php 73 | http://php.net/manual/en/function.xml-parse-into-struct.php 73 | http://php.net/manual/en/function.imagejpeg.php