PHP Manual
Language Reference
Basic syntax
Types
Variables
Constants
Expressions
Operators
Control Structures
Functions
Classes and Objects
Namespaces
Enumerations
Errors
Exceptions
Fibers
Generators
Attributes
References Explained
Predefined Variables
Predefined Exceptions
Predefined Interfaces and Classes
Predefined Attributes
Context options and parameters
Supported Protocols and Wrappers
Comments
Introduction
Language Reference
PHP Manual
Types
Table of Contents
Introduction
Type System
NULL
Booleans
Integers
Floating point numbers
Strings
Numeric strings
Arrays
Objects
Enumerations
Resources
Callbacks / Callables
Mixed
Void
Never
Relative class types
Singleton types
Iterables
Type declarations
Type Juggling