Windows 10 was released on 29th July 2015 and was made available as a free upgrade to those who had Windows 7 Home / Professional as well as Windows 8 / 8.1 Home / Professional. The free upgrade to Windows 10 is not made available to those running an enterprise edition of Windows 7 or Windows 8. Instead, these version of Windows only get a free upgrade to Windows 10 enterprise if they have software assurance attached to their licenses.
The upgrade to Windows 10 takes approximately 45 – 180 minutes depending on your internet connection speed and hard drive speed. If you have multiple Windows 10 compatible computers to upgrade, you may download the Windows 10 media creation tool, which will allow you to download an ISO of Windows 10 or do an in-place upgrade.
Some hardware drivers will need to be upgraded after installation and you will need to visit your manufacturers website for the latest drivers. However, Windows 10 has a large majority of drivers to get you PC operating straight away.
Overall I found the upgrade to Windows 10 quite an easy and seamless process and would recommend those who want to upgrade to do it.