title: C# UI on separate thread
body: <p>I keep seeing on various forums, tutorials or SO answers a recommendation to run the UI on a separate thread then the rest of the program to keep it responsive.<br>
  How is this done in practice? Does it mean editing <code>program.cs</code> to start a thread before loading the form? Or does it mean that any non-trivial operation activated from within the form fork a thread and use that? Or is it some setting? How do you work with it??</p>