If you have a valid Windows 7 or 8 license, you can upgrade it to Windows 10 for FREE! Visit the Microsoft Software Download Windows 10 page from a Windows 7, Windows 8.1 or Windows 10 device, and use media creation tool to upgrade to Windows 10 for FREE.
Click here to view all Microsoft offers.
Do not do it until you are sure the windows 10 upgrade is bug-free. After seeing this post I upgraded and my photos and email client stopped working.. it took me a day to revert to the previous version and fix all the problems the upgrade caused.