Windows is rolling out Windows 10 Wednesday, July 29, and critics are already singing praise.

The upgrade is free for existing Windows users for the first year and then will cost $120. It includes a move away from Windows 8's touch-based programming, which was deemed cumbersome by users.

Upgrades include the return of the iconic Start menu in the lower left-hand corner, which was lost in Windows 8. It also features an "Action Center," which consolidates all notifications from the various apps used on the computer.

Another new feature, "Hey Cortana," acts as a Siri-like virtual assistant, allowing users to "simply holler questions at your laptop," according to tech blog The Verge.

Windows 10 also has an interface to simultaneously search for files locally via the computer and on the Internet.

This is Microsoft's last complete upgrade overhaul, according to the company, and all further changes will be revisions or changes to the 10 platform.