Upgrading operating systems is always an exciting event, it almost feels like the device you’re upgrading gets a breath of fresh air. The good news is that anyone running Windows 7 or Windows 8/8.1 will be able to upgrade to Windows 10.
This means that those users will not need to backup all their personal files as the upgrade process will leave them intact, although it’s always recommended to do so just in case. The same goes for personal OS settings. Unfortunately for those running Window Vista, XP or older, a complete format will be required, so all files and settings will be lost according to Microsoft's Gabriel Aul.
@Dave_256 Same for Vista as XP. The only full upgrade paths currently supported are Win7 and newer.
— Gabriel Aul (@GabeAul) December 30, 2014
A few months ago, Microsoft was testing the distribution of the Windows Technical Preview via Windows Update, and if the results of the test are all positive, the final version of Windows 10 may be delivered this way, possibly as a free upgrade. This should make it really easy for those running the current and last generation version of Windows to get the latest version. If you recall, Microsoft has also delivered the Windows 8.1 upgrade via the Windows Store, so that’s an option too.
Windows 10 will be ready for release in the second half of the year, but in the meantime, there is still the January Technical Preview and the Microsoft event happening later this month to look forward to, so stay tuned!