title: When and why would you seal a class?
body: <p>In C# and C++/CLI the keyword <code>sealed</code> (or <code>NotInheritable</code> in VB) is used to protect a class from any inheritance chance (the class will be non-inheritable). I know that one feature of object-oriented programming is inheritance and  I feel that the use of <code>sealed</code> goes against this feature, it stops inheritance. 
  Is there an example that shows the benefit of <code>sealed</code> and when it is important to use it?</p>