Specifically, Microsoft is no longer peddling copies of the Home Basic, Home Premium or Ultimate versions of Windows 7 to customers. Windows 8 is also no longer available at retail from Microsoft, as the Redmond-based giant just wants it to go away at this point. Of course, you can still buy Windows 8.1 from Microsoft, which already has a larger market share than Windows 8.
Many retail stores will still have stocks of the older versions of Windows so it is not impossible to buy a genuine copy just yet, and probably won't be for a while. Microsoft is hoping that the 2015 launch of Windows 10 will let it put the Windows 8 fiasco to bed and move on, but it also has to convince Windows 7 users that there is a need to upgrade.