There are two kinds of types in C#:
value types
reference types.
Variables of value types directly contain their data.
Variables of value types have their own copy of the data.
Variables of reference types store references to their data(objects).
Variables of reference types may reference the same object.
C#'s value types includes:
simple types
enum types
struct types
nullable types
C#'s reference types are:
class types
interface types
array types
delegate types.
The following table lists the concrete types and their group names:
Signed integral sbyte, short, int, long
Unsigned integral byte, ushort, uint, ulong
Unicode characters char
IEEE floating point float, double
High-precision decimal decimal
Boolean bool
Enum enum EnumTypeName {...}
Struct struct StructTypeName {...}
Nullable value type nullable value