Microsoft is going to start its Windows 10 Anniversary Update rollout today, this is going to be the first major feature update for the operating system since it was publicly launched a year ago. Full details about the main new features can be read at The Windows Blog.
We are committed to delivering continuous innovation to you: including features that bring Windows Ink and Cortana to the mainstream; a faster, more accessible and more power-efficient Microsoft Edge browser; advanced security features for consumers and enterprises; new gaming experiences and new tools for the modern classroom. Everyone running Windows 10 will get these new features for free.
By the way, if you haven't upgraded to Windows 10 yet, there's still a loophole available to get the upgrade for free.