Facebook may know a lot about you, but they aren’t directly hooked up to your brain ... yet.

The company announced last week that their research and development team, known as Building 8, is currently developing technology to allow users to type words onto a computer with their minds.

That announcement is raising some eyebrows, but the technology isn’t as strange as it might seem.

Their proposed device is classified as a brain-computer interface (BCI), which sounds like something out of science fiction.

However, the technology has actually existed, in some capacity, for decades.

Development of BCIs, in fact, has been ongoing since the 1960s.

In one landmark demonstration from 1988, volunteers were able to use a device to spell words on a computer screen for the first time .

Facebook’s announcement is largely a continuation in this line of development.

The real emphasis is not merely the ability to do the typing, but the speed of that typing.

Company officials say their device would allow people to spell out words with their minds at a dramatically faster speed than previously possible — supposedly up to 100 words per minute.

That’s pretty fast, even on a keyboard — and certainly faster than prior BCI iterations.

Facebook isn’t the only place where this technology is being tested.

In another prominent experiment, Jaimie Henderson, a neurosurgeon at Stanford University, recently told Scientific American, “We're approaching half of what, for example, I could probably type on a cell phone.”

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How the technology works

As far as BCIs go, the technology has been slow to garner widespread use.

It sometimes is called an “” because it is expensive, cumbersome, and currently with limited applications.

So far, the technology has largely has been relegated to small spheres of medical usage — namely as a possibility to help severely paralyzed individuals or those with certain severe neurological conditions like Parkinson's disease.

As the name suggests, a BCI is often directly hooked up to the brain, requiring an implant in the skull for it to work.

“There's obviously significant medical risk to having a physical device permanently implanted in your brain,” Dr. Henry Mahncke, a neuroscientist and chief executive officer of Posit Science, told Healthline. “It's a surgical procedure to put the device in, and a chronic physical risk to the brain to have a foreign object embedded in it.”

Facebook is hoping to change that, though.

They are working on a noninvasive BCI that would utilize brainwaves but without having to be physically embedded within the skull.

Instead, the unit could potentially be worn as cap.

The speed of the transfer of information between the brain and the BCI through the skull is of utmost importance to create a viable piece of medical equipment.

“There is a tremendous loss of accuracy,” when measuring brain activity outside of the skull compared with using an embedded BCi, says Mahncke.

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Others jump in

Facebook isn’t the only major technology company to recently announce an interest in BCIs.

Elon Musk’s newly formed company, Neuralink, is also developing its own interface device, as is Kernel, a company founded by entrepreneur and venture capitalist Bryan Johnson.

But, Musk is also keenly aware of the challenges that this type of technology represents.

“It's mostly about the bandwidth, the speed of the connection between your brain and the digital version of yourself, particularly output,” he told The Verge.

BCIs simply have not found much use yet, because the typing speed output was too slow.

There are also questions about how the devices could be developed for use beyond the medical sphere.

Musk has already made clear his belief in the potential value for such devices in everyday life, allowing users to have their brains hooked up to the internet, for example.

But, that’s still a long way off.

Mahncke, for his part, believes that disruptive technologies like BCIs will always have their supporters and detractors.

“All new broadly adopted communication technologies cause societal change … People complain that the technology has ruined society, and others say that they can't imagine life without it,” he said.

“These technologies,” he added, “will both be revolutionary and no different. If used for the best, they will expand us as humans — how we interact with the world and how we connect with each other.”

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