The fisher cube is a 3x3 shape mod that looks similar to a regular 3x3, but isn't.
The fisher cube looks like a regular rubik's cube.
It's named after Tony Fisher.
What looks like second layer edges are actually centers. Because of that, some centers end up rotated. Unlike picture cubes though, the fisher cube can have one center roatated 90 degrees.
What looks like centers or corners are actually edges.
What look like first layer and last layer edges are actually corners.
After doing some PLL's, the center gets rotated.