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 14.2% of the 6111 total user notes.
Notes | Page -------+--------------------------------------------------------- 103 | http://php.net/manual/en/function.setcookie.php 90 | http://php.net/manual/en/ref.session.php 52 | http://php.net/manual/en/language.oop.php 46 | http://php.net/manual/en/function.preg-replace.php 43 | http://php.net/manual/en/ref.imap.php 43 | http://php.net/manual/en/function.include.php 43 | http://php.net/manual/en/ref.pdf.php 43 | http://php.net/manual/en/ref.datetime.php 42 | http://php.net/manual/en/function.mail.php 40 | http://php.net/manual/en/ref.image.php 39 | http://php.net/manual/en/features.file-upload.php 37 | http://php.net/manual/en/function.exec.php 37 | http://php.net/manual/en/function.fopen.php 33 | http://php.net/manual/en/language.variables.predefined.php 31 | http://php.net/manual/en/ref.oci8.php 30 | http://php.net/manual/en/ref.domxml.php 30 | http://php.net/manual/en/function.odbc-connect.php 30 | http://php.net/manual/en/function.str-replace.php 29 | http://php.net/manual/en/function.mssql-connect.php 28 | http://php.net/manual/en/function.date.php