If you are not ready to upgrade to Windows 10 this summer you can keep it from downloading and prompting you to install the upgrade.



From Supersite for Windows:

Microsoft has confirmed that the new OS, currently in its final stages of development, will be made available for download/install on eligible systems on 29 July 2015.

In preparation for that, back in April, Microsoft released an optional update (KB3035583) for Windows 7 and 8.1 that is called the Get Windows 10 app. It provides the prompt that started appearing on users systems (Windows 7 and 8.1) yesterday and gives you the option to reserve your copy of Windows 10.

  How to stop the Windows 10 Upgrade from downloading on your system