An archtop guitar is a steel-stringed acoustic or semi-acoustic guitar with a full body and a distinctive arched top, whose sound is particularly popular with jazz players.
The archtop guitar is often credited to Orville Gibson, whose innovative designs led to the formation of the Gibson Mandolin-Guitar Mfg. Co, Ltd in 1902. It was later redesigned by Lloy Loar. Originally all of them were acoustic , from the XX century we start to see electric models.
Archtop guitar has arched top and back, not flat, and similar F-holes to the members of the violin on which they were originally based. On the other hand, it normally has 6 strings heavier for reasons of tone and its body needs to be solid due to the tension that has to support the neck.