Value Types and Reference Types
A data type is a value type if it holds the data within its own memory allocation. A reference type contains a pointer to another memory location that holds the data.
Reference types include the following:
String
All arrays, even if their elements are value types
Class types, such as Form
Delegates
You can assign either a reference type or a value type to a variable of the Object data type. An Object variable always holds a pointer to the data, never the data itself. However, if you assign a value type to an Object variable, it behaves as if it holds its own data. For more information, see Object Data Type.
You can find out whether an Object variable is acting as a reference type or a value type by passing it to the IsReference method on the Information class in the Microsoft.VisualBasic namespace. Information.IsReference returns True if the content of the Object variable represents a reference type.