Microsoft has officially announced Windows 10 S Mode, an evolution of Windows 10 S as an idea. When Windows 10 S was announced last year, it was released as a standalone edition of Windows 10 that was available alongside Windows 10 Home, Windows 10 Pro, and Windows 10 Enterprise. Now, however, Microsoft is making Windows 10 S a mode that runs on top of Home, Pro, Education, or Enterprise, instead.

Today, Microsoft further detailed this change. Based on feedback from partners and customers, Microsoft says the decision to make Windows 10 S a mode instead of a standalone edition of Windows 10 is to help minimize confusion between the separate editions. Windows 10 S is designed to keep your PC secure and fast, which should be applicable to all editions of Windows 10.

As such, Microsoft is opting to allow partners to load new devices with Windows 10 Home or Pro, and optionally have those devices ship with S Mode enabled. S Mode is exactly the same as what Windows 10 S was when it was a standalone edition, except now it runs on top of Home or Pro instead. What's more, Microsoft says that S Mode devices will be able to switch to their respective full editions for free, even if the device ships with Windows 10 Pro in S Mode.

We expect the majority of customers to enjoy the benefits of Windows 10 in S mode. If a customer does want to switch out of S mode, they will be able to do so at no charge, regardless of edition. We expect to see new Windows 10 devices ship with S mode, available from our partners in the coming months, so check back here for updates.

That's a huge deal, and is excellent news for everybody. No longer will people buying Windows 10 S machines be required to pay for an upgrade to the full edition of Windows 10 if they need to install a program from outside the Store. That upgrade is now free, forever, meaning the user won't feel forced to do it if the upgrade is free for a limited time. It'll be there to switch to whenever the user needs it, which is a much better.

Microsoft says these changes to Windows 10 S will be put into effect with the next update to Windows 10. It's not clear if this will be with Redstone 4, or Redstone 5 however. Existing Windows 10 S users will be automatically moved to Windows 10 Pro in S Mode, meaning existing S users won't be missing out on any of the benefits Windows 10 S provides.