This document provides examples and explanations of various PHP functions for working with strings, numbers, and other data types. It includes functions for string manipulation like substr(), str_replace(), strpos(), explode(), and implode(). Numeric functions demonstrated include type checking, conversion between binary, octal, hexadecimal and decimal numbers. Other functions covered are trim(), list(), printf()/sprintf() for formatting output, and math functions like floor(), ceil() and round(). Examples are given for each function to illustrate its usage.