What kind of vehicle is defined as having no frames around the windows?

The vehicle defined as having no frames around the windows is a hardtop. Hardtop cars typically have a fixed roof and are distinguished by the absence of door frames and window frames, which creates a sleek, continuous appearance. This design not only enhances aesthetics but can also provide a more spacious feeling inside the cabin, as the windows tend to be larger.

Hatchbacks, convertibles, and coupes have distinct characteristics that differentiate them from hardtops. Hatchbacks are known for their rear door that swings upwards, convertibles feature a retractable roof, and coupes are typically two-door vehicles with a fixed roof and often a sleek profile. However, it is the hardtop that specifically lacks the frame surrounding the windows, solidifying its identity in the automotive world.