On September 30, 2014, Microsoft announced Windows 10, thus changing the firm's operating system as we know it. Windows was going to be serviced, rather than being refreshed every few years. We've learned since then that this means biannual feature updates, along with monthly (sometimes more often) cumulative updates.

Indeed, Microsoft was done competing with itself with new versions of Windows. On July 29, 2015, Windows 10 launched, and it was promised that there would never be a Windows 11. Here we are, exactly three years later, when we would normally see the next version of Microsoft's flagship OS.

Since then, there have been five feature updates, including versions 1511, 1607 (the Anniversary Update), 1703 (the Creators Update), 1709 (the Fall Creators Update), and 1803 (the April 2018 Update). Much has changed, and a lot of the OS looks completely different from when it started out.

 

https://www.neowin.net/news/windows-10-turns-three-years-old-today-heres-how-its-evolved