Recently users of Windows 7 and 8 have been seeing a popup in the bottom right of their screen. This popup is offering a free update to Windows 10 when it becomes available.
From past experience I would not recommend accepting this offer. No one knows just how this update will affect your existing programs. After the update your email, backup or accounting programs may not function. There are so many potential problems that it is not worth the risk.
The best option would be to wait until after the release and all the bugs have been worked out. Then after making a backup of your system we could update Windows.