Introduction

PHP supports eight primitive types.

Four scalar types:

• boolean
• integer
• float (floating-point number)
• string

Two compound types:

• array
• object

And finally two special types:

• resource
• NULL

This manual also introduces some pseudo-types for readability reasons:

• mixed
• number
• callback

And the pseudo-variable $....

The type of a variable is not usually set by the programmer; rather, it is decided at runtime by PHP depending on the context in which that variable is used.