The video shows you how it is possible to be running windows and mac in parallel. Both operating systems, mac and windows, are installed in the computer and the video shows us how one can flip back-and-forth between operating systems. First the video shows us the desktop for mac and then the image flips, as if it were a cube, and it shows us the desktop for windows. Then the video flips again between both systems, but this time there's a demonstration where some windows are opened and some work is performed using the opened windows in both operating systems to demonstrate how this can be done. The video ends by showing us a link to http://lifehacker.com with more information on how this can be done.