(PHP 4, PHP 5, PHP 7) Calculate the metaphone key of a string

(PHP 4 >= 4.0.2, PHP 5, PHP 7) Binary safe case-insensitive string comparison of the first n characters

(PHP 4, PHP 5, PHP 7) Get string length int strlen

(PHP 4, PHP 5, PHP 7) One-way string hashing

(PHP 4, PHP 5, PHP 7) Split a string by string

(PHP 4, PHP 5, PHP 7) Quote regular expression characters

(PHP 4, PHP 5, PHP 7) Convert binary data into hexadecimal representation

(PHP 4, PHP 5, PHP 7) Un-quote string quoted with

(PHP 4, PHP 5, PHP 7) Convert special characters to HTML entities

(PHP 4, PHP 5) Replace regular expression string