The original RTM version of Windows 10 was released on July 29 back in 2015. Since then, Microsoft has released 3 major updates for the Windows 10 platform, including the recently released Creators Update (version 1703). At the same time, the original Windows 10 has received a bunch of cumulative updates, including security fixes and stability improvements. However, Microsoft is now supporting its frequently updated products for 18 months or 1.5 years, and the time for Windows 10 ver. 1507 support to end is almost up.
If you're still running the original version of Windows 10 that was introduced back in July 2015 (version 1507) and for some reason still ignoring all of the offered major updates for it, Microsoft is giving you two extra months to decide if you want to get future patches and security updates. The updated end-of-life date now states 'May 2017' compared to the previous March 26 schedule. All machines running Windows 10 1507 (build 10240) will continue to get updates during that period.
Microsoft has published the final version of Windows 10 for free download. You can download it via Windows Update and start using it. Here is where to download and how to upgrade to Windows 10.
As Windows 10 is finalized, Microsoft has released a new build for Windows Insiders. This release is notable and different from previous releases because Windows 10 build 10240 is from the RTM (Release to Manufacturing) branch. So, you will not find a watermark on the desktop in this build and the user experience will be like the final version of Windows 10.
Here is good news for everyone who is expecting Windows 10 RTM. It might be done this week. Windows 10 has reached the release candidate (RC) stage. So, if Microsoft decides that the operating system is good enough for daily use, it will be signed off.
Microsoft officially announced that Windows 10 will be available after July 29. Starting from that date, you will be able to buy new hardware with pre-installed Windows 10 or receive your digital copy of Windows 10 which you might have reserved in advance.