Hollow body electric guitars (also known as semi-acoustic guitars) are mainly used by Jazz and Blues guitarists. The more popular hollow bodies are made by guitar manufacturers such as Gibson, Gretsch and Rickenbacker.
They differ in various ways, such as shape, the thickness of the body and the amount of cut-aways in the body. A noticeable difference between a hollow body electric and a solid body electric is the use of a fixed bridge tailpiece, sometimes joined to the bottom of the guitar body, as part of the strap pin.
Most hollow body electrics have soundholes in the same way a classical or steel string guitar has. A common hollow body soundhole style is the f-hole as shown in the photo below.