Google registered the brand pigweed, a supposed new operating system.

Google registered a trademark for the name Pigweed in January 31st. with is supposed to be a new operating system.  The document does not give details about Pigweed, but it I know that it has appeared related to the operating system Fuchsia, which is in development.

Fuchsia is an upcoming mobile operating system that will combine features from Android and Chrome.

At this point Google has not announced informations about this supposed operating system. 

Source: Techradar