![](https://lemmy.ml/pictrs/image/a64z2tlDDD.png)
There's a video introduction that talks a little about it and shows a bit of usage.
The canonical proprietary version of this is the SpaceMouse.
These are used in concert with a traditional mouse, with the 3d mouse being used for navigation of the 3d space. They have six degrees of freedom (as in, you can rotate in any axis or you can push it in any axis) so you can rotate and you can pan any which way with full control.
If you've ever gotten frustrated in a 3d program trying to figure out the correct sequence of rotations to get to your preferred view, that's the use case the 3d mouse addresses.
My only complaint is the suggestion that engineers like to be clear. My undergrad classes included far too many things like
2 cos 2 x sin y