Ars Technica is reporting that Google is developing a third open source operating system, in addition to Chrome OS and Android. Called Fuchsia, the new OS isn't based on Linux like Android and Chrome; instead, it uses a new kernel called Magenta. According to the report, Fuchsia is meant for "modern phones and modern personal computers with fast processors, non-trivial amounts of RAM with arbitrary peripherals doing open-ended computation."
It's impossible to know whether this new operating system will ever become available for public use. However, a Google developer named Travis Geiselbrecht has said that Fuchsia "isn't a toy thing, it's not a 20% project, it's not a dumping ground of a dead thing that we don't care about anymore."