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

(PHP 4 >= 4.2.0, PHP 5, PHP 7) Calculates the md5 hash of a given file

(PHP 4, PHP 5, PHP 7) Replace text within a portion of a string

(PHP 4, PHP 5, PHP 7) Tokenize string string

(PHP 4 >= 4.2.0, PHP 5, PHP 7) Perform the rot13 transform on a string

(PHP 4 >= 4.1.0, PHP 5, PHP 7) Return a formatted string

(PECL bbcode >= 0.9.0) Create a BBCode Resource

(PHP 4, PHP 5, PHP 7) Strip whitespace (or other characters) from the beginning of a string

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

(PHP 4, PHP 5, PHP 7) Parses the string into variables