Neuralink is working on a kind of brain-computer interface that it hopes will one day help restore brain functions in humans with disorders like blindness, seizures, and insomnia.

Musk’s experimental technology is still in its early stages. And it has yet to be tried on humans. But Musk pitched it as glimpse into the near future, without acknowledging the immense technological or regulatory challenges.

During the livestreamed event, Neuralink staff showed off three pigs—one normal pig, one implanted with Neuralink’s device, and another that had the device removed from its skull.

Hesitant to leave its pen at first, Gertrude—a pig that has had its implant for two months—slowly walked within its small enclosure, sniffing hay. All the while, the technology recorded its brain activity and displayed it on a large screen.

Each of Gertrude’s sniffs produced what sounded like video-game beeps, which Musk said were audio representations of Gertrude’s brain activity. “Whenever she shuffles around and sniffs things with the snout, that sends out neural spikes,” Musk said.

The demonstration was intended to show that the high-profile startup’s technology works, even if only at a basic level, inside the brain of a living animal. Creating technology that could actually impact what an animal does could take years to accomplish, if ever.

Here are three takeaways from the event:

What can the technology do today?

Musk said that his technology can already predict the position of all of a pig’s limbs with high accuracy. Being able to do so is an important but early step to help an animal regain movement in an injured or paralyzed limb.

In describing a pig that had two Neuralink implants, Musk said his team wanted to prove that a living creature can have multiple devices implanted without them being visible. Having several implants could help, presumably, to help the brain perform different tasks.

As for the pig that had no longer has an implant, Musk said that was intended to show that the device can be removed without leaving any noticeable scars or neurological damage. 

What does the implant look like?

The device revealed on Friday resembled a small keychain affixed to an oversized penny. 

Musk said that the devices may be implanted on the surface of human brains using a surgical robot that resembles a large sewing machine. The implants would have sensors like a smartphone that can record health information like body temperature.

“In a lot of ways it’s like Fitbit in your skull with tiny wires,” Musk said.

He said the surgical procedure would last less than one hour and that it would require no general anesthesia. The process, he said, should only leave a “tiny scar” on a person’s head. 

The device would function around the clock and charge at night, though Musk didn’t say how. It would connect online via the Bluetooth wireless technology to a smartphone app, though a Neuralink staff member conceded that the signal would be weaker in crowded locations like concerts where many people are using Bluetooth devices. He did not say what would happen in such a scenario.

What is the implant supposed to do?

Musk said he wants to eventually conduct a clinical trial on people who suffer from tetraplegia, a type of paralysis caused by spinal cord injuries. The hope, he said, is to allow someone who is paralyzed to walk again.

Musk described this type of paralysis as caused by distorted electrical signals in the brain. In theory, with Neuralink’s technology, he said “you can jump over the broken wires” caused by a spinal injury to restore electrical signals in the brain so that people will regain the ability to walk. 

Besides its use in health care, Musk also intends for Neuralink’s technology to allow people to turn their thoughts into reality. For example, people would be able to instantly play their favorite song by thinking about it or summon a self-driving car. 

Musk also believes that people will be able to use the technology to save and replay memories. “You can store your memories as a backup,” Musk said. “You can potentially download them into a new body or a robot body.”

“The future is going to be weird,” Musk said.