Giving a glimpse of what is going on at its secret "Building 8" research group, Facebook has said it is working on a way to let people type with their brains -- at speeds faster than physical typing -- via a brain-computer interface.

"We are working on a system that will let people type with their brains. Specifically, we have a goal of creating a silent speech system capable of typing 100 words per minute straight from your brain -- that's five times faster than you can type on a smartphone today," Regina Dugan, Vice President of Engineering and "Building 8," told the audience at the annual F8 developers conference in San Jose on Wednesday.

Facebook announced two projects from "Building 8" that are focused on silent speech communications.

"Building 8" is the product development and research team at Facebook focused on creating and shipping new, category-defining consumer products that are social first.

Products from "Building 8" will be powered by a breakthrough innovation engine modeled after US Defense Advanced Research Projects Agency (DARPA) and shipped at scale, the company said.

Just like people take many photos and choose to share only some of them, Facebook's new project will decode words that people have already decided to share by sending them to the speech centre of the brain.   

"It's a way to communicate with the speed and flexibility of your voice and the privacy of text. We want to do this with non-invasive, wearable sensors that can be manufactured at scale," Facebook added.

The company also unveiled a project directed at allowing people to hear with their skin and it is building the hardware and software necessary to deliver language through the skin.