PHP supports eight primitive types.
Three scalar types:
Three compound types:
And finally two special types:
The type of a variable is usually not set by the programmer; rather, it is decided at runtime by PHP depending on the context in which that variable is used.
If you would like to force a variable to be converted to a certain type, you may either cast the variable or use the settype() function on it.
Note that a variable may behave in different manners in certain situations, depending on what type it is at the time. For more information, see the section on Type Juggling.