sedan seats four or more and has a fixed roof that is full-height up to the rear window. Most commonly it is a 4-door; 2-door is rarer but they do occur (more so historically). In the U.S., this term has been used to denote a car with fixed window frames, as opposed to the hardtop style where the sash, if any, winds down with the glass. As hardtops have become rarer, this distinction is no longer so important.
Coupés generally, but not necessarily, have two doors, although automobile makers have offered four-door coupés and three- and five-door hatchback coupés, as well.
A coupé is distinguished from a sedan primarily by interior volume; SAE standard J1100 defines a coupé as a fixed-roof automobile with less than 33 ft³ (0.93 m³, 934.6 L) of rear interior volume. A car with a greater interior volume is technically a 2-door sedan, not a coupé, even if it has only two doors. Some automakers may nonetheless choose to use the word coupé to describe such a model, e.g., the Cadillac Coupe de Ville.
A sport utility vehicle, or SUV, is a type of passenger vehicle which combines passenger-carrying and load-hauling abilities with the versatility of a pickup truck. Most SUVs are designed with a roughly square cross-section, an engine comportment, a passenger and cargo compartment, and no dedicated hood. Most midsize and large SUVs have 5 or more seats, and a cargo area directly behind the last row of seats. Small SUVs, such as the Jeep Wrangler, typically have less seats.
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