Microsoft is so keen on influencing people to upgrade to windows 10 that Windows 10 downloads to a hidden folder on your computer provided you're using Windows 7 or Windows 8/8.1 and you have automatic update turned on.

Although you don't have to install the update if you don't want to, the download is said to take up to 3.5 to 6GB of your disk space. Microsoft reason for this move is to "help upgradeable devices get ready" in case users decide to install Windows 10.

So for those of you so glued to your Windows 7 or Windows 8/8.1, Microsoft really wants you to upgrade...I think it's a cool move though.

http://www.thypcdoc.com/2015/09/lol-windows-10-by-force.html