Microsoft unveiled Windows 10 and revealed it is for free for existing Windows 8.1 users, Daily Mail reported.

The software upgrade will be for free for the first 12 months after it is officially released but it will last the lifetime of the device. Windows 10 will be available to all platforms including desktops, Xbox One game console and mobile phones. The good news is PC users can now see the comeback of the start menu.

Aside from that, Cortana will be available as a digital assistant that has seven languages as well as a "Yoda impersonation mode." It can help the user search for files in the computer by merely typing in some key words such as "photos taken in January" and results will pop up. Users can ask help form the Cortana in answering and sending emails and even controlling the media player, The Register reported.

As a replacement for Internet Explorer, the Windows 10 will have Spartan. The new browser is reportedly a Google Chrome competitor since it looks similar to the latter. Users can mark the pages of the websites directly and comment at the same time, according to The Next Web.

There is also a reading mode where internet articles will be downloaded automatically to read later when the user is offline.  This is a helpful feature for those who travel without internet access.

Other than that, developers will be happy to know that there is a platform where they can sell their applications called Universal Apps. Microsoft operating systems vice president Terry Myerson said that instead of "million sales," developers can now look forward to earning the "next billion."

Microsoft also unveiled the holoLEns, which is an "augmented reality headset" to run the software. The details of the device are not yet confirmed but it integrates virtual objects into the user's actual location. The user may see Skype windows or gaming environments integrated into the real world.

As of this time, 1.7 million people signed as beta testers for Windows 10. Microsoft expects more users as it continues to add new features into the software before its official release in fall of this year.