For those not in the know, hall-effect key switches can tell the analog position of each key, rather than only whether it's pressed or not as in traditional key switches.
The key/switch has a little magnet on the stem and the hall effect sensor is measuring the strength of the magnetic field as the magnet moves up/further & down/closer to the sensor.
Yes I recognize that. But I've seen hall-effect keyboard many, many times and magnetic keyboard never (before this post). I guess some company decided to call their keyboard a magnetic keyboard and now a specific subset of people think they're all called that - even though they've been called hall-effect keyboards since their inception.