Windows 7 worked on Windows 7. These were broadly divided into "core operating system" and "Windows client experience", in turn organized into 25 teams of around 40 developers on average. In October 2008, it was announced that Windows 7 would also be the official name of the operating system. There has been some confusion over naming the product Windows 7, while versioning it as 6.1 to indicate its similar build to Vista and increase compatibility with applications that only check major version numbers, similar to Windows 2000 and Windows XP both having 5.x version numbers. The first external release to select Microsoft
Windows Vista flops. Microsoft's then much smaller competitor Apple noted that, despite Vista's far greater sales, its own did not seem to have suffered after its release, and would later invest in advertising mocking Vista's unpopularity with users. Computer manufactures such as Dell, Lenovo, and Hewlett-Packard released their newest computers with Windows Vista pre-installed; however, after the negative reception of the operating system, they also began selling their computers with Windows XP CDs included because of a drop in sales. A Gartner research report predicted that Vista business adoption in 2008 would overtake that of XP during the same time frame (21.3%