How delegates work (in the background)?

Question

How do delegates work in c# behind the scenes and how can they be used efficiently?

EDIT: I know how they work on the surface(they are basically function pointers a

Answer 1

When you define your delegate

internal delegate void Feedback(Int32 value);

the compiler actually defines a complete class that looks something like this:

internal class Feedback : System.MulticastDelegate {  
   // Constructor  
   public Feedback(Object object, IntPtr method);  

   // Method with same prototype as specified by the source code  
   public virtual void Invoke(Int32 value);  

   // Methods allowing the callback to be called asynchronously  
   public virtual IAsyncResult BeginInvoke(Int32 value,  AsyncCallback callback, Object object);  

   public virtual void EndInvoke(IAsyncResult result);  
}

Source: Jeffrey Richter - CLR via C#, chapter 17