title: Enum is Reference Type or Value Type?
body: <p>I used Enum property in my <a href="http://msdn.microsoft.com/en-US/data/ef">EntityFramework</a> 5 class,
  but in the database this field is nullable. Visual studio gives the error that this property must be a nullable property. My question is: is Enum a reference type or a value type?</p>