PHP supports eight primitive types.
Four scalar types:
Two compound types: And finally two special types:Note: In this manual you'll often find mixed parameters. This pseudo-type indicates multiple possiblities for that parameter.
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.
Tip: If you want to check out the type and value of a certain expression, use var_dump().
If you simply want a human-readable representation of the type for debugging, use gettype(). To check for a certain type, do not use gettype(), but use the is_type functions.
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.