Beginning July 29, Windows 7 and Windows 8.1 users will be able to download Windows 10. It’s a monumental shift for both Microsoft and its customers. But Microsoft has provided a wealth of information to ease the transition, and let you upgrade to Windows 10 as simply and easily as possible. For consumers, the choice is a simple one: You’ll be upgraded to one of two versions of Windows 10: Windows 10 Home, or Windows 10 Professional. (This guide doesn't cover the upgrade process to Windows 10 Mobile for phones.) Microsoft has also released the official retail pricing for Windows 10 , in case you're building a your own PC. During the update process, plan to invest some time in prep work and at least an hour in the upgrade process itself. And be careful—some of your applications may be left behind.