It starts with an automated setup of Windows on a Mac. Then, there’s excellent integration between Windows and Mac — both ways, including:• same Desktop files on both;• associate and “Open with…” files with apps from the opposite OS, complete with icons;• save files from Windows apps directly into any folder in the Mac user Home folder;• dock Windows apps to Mac Dock, and Hide or Quit them as any other Mac app;• and finally, the Coherence Mode, which shows Windows apps visually isolated from Windows desktop, as if they are just another Mac app (though with trailing artifacts when moving or resizing them).(I mainly use it for Outlook and Remote Desktop, and have fine-tuned the OS-wide shortcuts in Parallels settings.)For frequent and serious use, the free Virtual Box simply doesn’t compare. Parallels Desktop Standard is definitely worth the $100 perpetual license.