Square inset
With this style cabinet, the doors fit flush into the face frame. It is commonly used with Shaker period styling.

Beaded inset
This is also a flush-fitting method, but a decorative wood edge (bead) is attached to the inside edge of the face frame that surrounds the door opening. This adds a little elegance to the simplicity of the above square inset.

Overlay
Doors may be set into (inset) the cabinets or may be placed standard over cabinets (overlay).