The data types ‎ANY‎ or ‎ANY_<type>‎ are used in interfaces of functions, function blocks, or methods in order to type input parameters whose type is unknown or unspecified: The input variables (‎VAR_INPUT‎) have a generic data type.

The compiler replaces the type of input variable internally with the data structure described below, whereby the value is not passed directly. Instead, a pointer is passed to the actual value so only a variable can be passed. Therefore, the data type is only specified when it is called. As a result, calls of such POUs can be made using arguments which each have different data types.