How does one fully remove McAfee?

Recently I downloaded a pdf document in chrome, and a banner appeared at the top of the browser window saying that McAfee Webadvisor was scanning the file. Interesting, because I did not install it. So I go to add remove programs, and uninstall anything that I see that is McAfee related. A couple of days later, the fan in my pc is spinning louder than usual, so I open up task manager, and lo and behold - the resource hog is non other than McAfee Webadvisor. Question: how does one completely remove every trace of McAfee from a Windows PC, and ensure that it does not reappear?