PHP Manual
Language Reference
Basic syntax
Types
Variables
Constants
Expressions
Operators
Control Structures
Functions
Classes and Objects
Namespaces
Exceptions
Generators
References Explained
Predefined Variables
Predefined Exceptions
Predefined Interfaces and Classes
Context options and parameters
Supported Protocols and Wrappers
goto
User-defined functions
Language Reference
PHP Manual
Functions
Table of Contents
User-defined functions
Function arguments
Returning values
Variable functions
Internal (built-in) functions
Anonymous functions