The type System.Array is the abstract base type of all array types. An implicit reference conversion (13.1.4) exists from any array type to System.Array, and an explicit reference conversion (13.2.3) exists from System.Array to any array type. Note that System.Array is not itself an array-type. Rather, it is a class-type from which all array-types are derived. At run-time, a value of type System.Array can be null or a reference to an instance of any array type.