After months of waiting, the follow up to Windows 8.1 is finally out. Millions have been busy downloading it overnight either automatically through Microsoft's reservation system or manually by installing it from ISOs.
The upgrade, which is free for genuine Windows 8.1 and Windows 7 SP1 users for a whole year, has been tested by more than five million users and is now available in 190 countries.
Windows 10 is being rolled out in waves, so you may not be able to download it straight away. You need to make sure your computer is up to date, so head over to Windows Update and accept any remaining updates.
After that you may see a Windows 10 icon in the bottom-right hand side of the task bar. When it appears, click it and select the option to reserve your copy of Windows 10. Once it's ready to download you'll see a notification pop up in the same corner.
Windows 10 has received a "4.5 out of 5" star rating in our review and has been hailed as the new Windows 7, being robust, pleasant to use and free for a lot of us.
Microsoft tweaked the operating system formerly known as Windows 9 and integrated a number of innovative experiences including Cortana, a new personal digital assistant, Internet Explorer's replacement, Edge, Integrated Xbox app, Continuum and Hello, an innovative authentication system.
More than 100,000 staff members from tens of thousands of stores worldwide have been trained to answer questions (like the ones our readers asked in our Windows 10 Q&A).