http://www.techradar.com/news/android-oreo-features-release-date

Update: Google has unveiled Android Oreo, its latest major operating system update that will be the backbone of Android devices moving forward. The fleet of Pixel and Nexus devices are the first to be supported, but many companies, including HTC, have confirmed that its recent flagship phones will be updated to Android Oreo.

Android Oreo is the official name of the next version of Google’s mega-popular mobile operating system that's available now for select devices.