Fuchsia is a new operating system Google’s been working on for many months. The Google Pixelbook is the notebook equivalent of a Google Pixel smartphone, instead running Chrome OS right out the box. Fuchsia is a brand new mobile operating system that is being built from the ground up. Where as Android and Chrome OS are built on Linux kernels, Fuchsia is built on Google’s own Zircon kernel. It even uses Google’s in-house programming language, so the platform is 100% Google from top to bottom. There’s no guarantee at this point that Google is planning to take Fuchsia beyond anything but IoT devices, but there’s a possibility that down the road it could be used to replace Chrome OS and Android. In the mean time, it’s more likely we’ll see Fuchsia used on future IoT devices like Google Home and hardware that doesn’t need to run Android. you can play around and check out the details on Fuchsia on its GitHub page and on Google Git, and it looks like it will soon support the Raspberry Pi 3.