The Android 8.0 release includes Project Treble, a major re-architect of the Android OS framework designed to make it easier, faster, and less costly for manufacturers to update devices to a new version of Android. Treble is for all new devices launching with Android 8.
How does it work?
Project Treble separates the vendor implementation from the Android OS framework via a new Vendor Interface. With Treble, a new stable vendor interface provides access to the hardware-specific parts of Android, enabling device makers to deliver new Android releases simply by updating the Android OS framework.