Right click the Skype system tray icon and click "Quit Skype"

How do you close Skype?
Based on the name and my understanding of the TF2 class, a Heavy is a front-lines tanky soldier guy. But that doesn't really seem to be his role in XCOM. Assault soldiers are better at being in the front lines with their mobility and defensive abilities.

What, then, is the heavy supposed to be doing on the battlefield? What are the general strategies that are useful for heavy soldiers?
