Value type - bool, byte, decimal, double, enum , float, 
int, long,  short, strut, uint, ulong,
 Value types are stored in the Stack
Reference type - class, delegate, interface, object, string
Reference types are stored in the Heap

Value types : Value types directly contain their data, and 
instances of value types are either allocated on the stack 
or allocated inline in a structure. Value types can be 
built-in (implemented by the runtime), user-defined, or 
enumerations. 

Reference types : Reference types store a reference to the 
value's memory address, and are allocated on the heap. 
Reference types can be self-describing types, pointer 
types, or interface types. The type of a reference type can 
be determined from values of self-describing types. Self-
describing types are further split into arrays and class 
types. The class types are user-defined classes, boxed 
value types, and delegates.

Variables that are value types each have their own copy of 
the data, and therefore operations on one variable do not 
affect other variables. Variables that are reference types 
can refer to the same object; therefore, operations on one 
variable can affect the same object referred to by another 
variable. All types derive from the System.Object base type.

Value type-
  1)Direct Contain their data.
  2)Operation on one variable don't effect the other variable
  3)int,short,structure,enum
Reference type-
  1)store the refrence to the data.
  2)operation on one variable can effect the other
  3)Classes,Array,Delegates