Why would I need to use a virtual modifier in a c# class?
<p>I have the following class:</p>

<pre><code>public class Delivery
{
// Primary key, and one-to-many relation with Customer
   public int DeliveryID { get; set; }
   public virtual int CustomerID { get; set; }
   public virtual Customer Customer { get; set; }

// Properties
   string Description { get; set; }
}
</code></pre>

<p>Can someone explain why they Customer information is coded with virtual. What does it mean?</p>
