Archtop guitars are a type of acoustic guitar characterized by their curved top and back, which enhances sound projection and tonal quality. They typically feature f-holes, similar to those found on violins, allowing for better resonance. These guitars are often used in jazz and blues music due to their warm, rich sound. Most archtop guitars have a hollow body, but some models are semi-hollow, combining features of both electric and acoustic guitars. Notable brands include Gibson and Epiphone, which have produced iconic models like the Gibson L-5. Their unique design makes them popular among musicians seeking a distinct sound.