I'm reading a Fine Woodworking book on "Boxes, Carcases, and Drawers." It's just a collection of articles from the early days of FWW. One of them is by Tage Frid, one of the major authors of the day. He writes, "Furniture construction is broken into two main categories: frame and carcase. In frame construction, relatively narrow boards are joined -- usually with a mortise and tenon joint -- as in a chair or table base, or a frame and panel door. In carcase construction boards are joined end to end using dovetails, tongue and groove joints and the like, as in a drawer or hutch."
Seems simple enough, huh?