Slab:
If you like clean lines, a slab door may be the choice for you. A flat door that essentially looks like a “slab” of wood, these doors eschew decorative raised or recessed panels. However, you can add a little pizzazz by routing a detailed edge profile if your door is made of MDF.
 

Raised Panel:
A raised panel, generally formed by joining several pieces of solid stock lumber with adhesive, is secured to the door's frame. The panel generally measures between 1/2" and 3/4" in height, giving it a flush or protruding quality, respectively. A routed edge profile tends to give the door a more elegant appearance.
 

Recessed Panel:
The recessed panel door is a flat panel affixed inside a frame constructed with miter or mortise and tenon joints. The resulting appearance has a picture frame-type look and a simpler, more country or Transitional appearance.
 

Curved Panel:
The top portion of this door’s decorative panel curves upward in a gentle arch. The panel itself is generally raised.
 

Cathedral Panel:
A cathedral-type arch is incorporated into the upper rail of this raised or recessed panel.
 

Beadboard Panel:
Typically found in a recessed panel, beadboard uses routed beaded details to create a causal country style.
 

Routed: 
A single piece of engineered wood material (such as MDF) is shaped to take on the appearance of a recessed or raised panel within the door, then painted or covered in laminate.