Descriptive car terms change and shuffle as new designs come out. GM used the term Convertible Hardtop, this used to confuse me because it was not convertible, like the Ford Skyliner. However, when you think about it as if they took a convertible car without door frames and then placed a Hardtop on the convertible, it makes sense. Marketing terms then confuse the issue by calling a four door hardtop a “Sport Sedan” The pictures above are labeled using the descriptive terms I prefer to classify roof styles.
Lots more Sedans, Hardtops, Convertibles and Station Wagons at my Flickr site: https://www.flickr.com/photos/greggjerdingen/collections/72157631550277505/