If you buy a refurbished laptop or a refurbished computer from GigaRefurb. Which is preinstalled with windows 7, You are eligable for a FREE upgrade to Windows 10
Windows 10 if familiar to use its alot like windows 7 with lots of improved features. It includes a new start menu and a new browser called microsoft edge.
It very easy to upgrade and you will be able to keep all your personal files and data.
This generous offer from microsoft is valid for the first 12 months of release of windows 10. so dont hang around. Upgrade for free.
You Can find out more here direct for the microsoft site.