The Inquirer was nice enough to compile a list of requirements to get a free upgrade to Windows 10, based on the rather confusing information which is being provided by Microsoft.  Windows XP and Vista users as well as any and all Enterprise customers will have to pay; prices are expected to be similar to previous releases.  If you run Win7 then you have until 27 July 2016 to click that little upgrade icon to reserve your copy for installation once the new OS is released.  If you are running Win8 then you must upgrade to Win8.1, from there you are qualified.  If you ran the beta, as in you were a member of the Windows Insiders Programme, it depends on your current Windows license, the fact that you tested will not grant you a free copy of Windows 10.  If you pirated or have lost your key then you are SOL, as are those running Linux as The Inquirer amusingly points out.

"MICROSOFT has been a little less than helpful in clarifying the terms of the free Windows 10 upgrade offer, and The INQUIRER is here to help."

Here is some more Tech News from around the web:

Tech Talk