This image provided by Microsoft shows the start menu of Windows 10, the company’s next version of its flagship operating system. The company is skipping version 9 to emphasize advances it is making toward a world centered on mobile devices and Internet services. Credit: Microsoft

Missing: Microsoft operating system. Went by the name “Windows 9.” Has disappeared without a trace.

Last month, in a surprise move, Microsoft announced that its next major operating system for computers and tablets will be called "Windows 10." It is the successor to Windows 8, the software currently shipping with many new PCs and tablets. Did we miss something? What happened to Windows 9?

Microsoft is mum on the omission, saying only that Windows 10 "represents the first step in a whole new generation of Windows." It is due in late 2015, but a technical preview is already being offered as a free download for brave early testers.

Is Microsoft trying to put as much (numerical) difference between this new software and Windows 8, which has proven divisive even among PC loyalists, as possible? Some speculated that coding bugs could have arisen had Microsoft stuck with the name "Windows 9" — some programming might have had trouble distinguishing it from older software such as Windows 95 or Windows 98.

Whatever the reason, if you’ve been waiting for Win 9, I’m sorry to tell you: It’s just not gonna happen.

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