Shaker style cabinets get there name from the simple shaker style furniture built by the Shakers in the late 1800s in the eastern USA.
Today, five-piece flat panel doors, on modern European-style, frame-less cabinets, painted white, are often thought of as being a typical shaker style. That would be a modern shaker interpretation.
A traditional shaker cabinet would have been a face frame cabinet with recessed flat-panel doors and flat slab drawer fronts which may be inset or overlaying the face frame. Something like this. The width of the stiles and rails of the frames were likely narrower, but you get the idea.
The photo on the left photo is taken from the very first project we built for clients in North Vancouver, British Columbia.