Lap slide guitars, the first developed, which use a similar sound box to a Spanish guitar. These were originally called Hawaiian guitars and included versions that had a factory raised nut, but also included Spanish guitars with a nut extender.
Resonator guitars, particularly those with square necks, but would include round neck versions with a raised nut.
Electric lap steel guitars, which include the first commercially successful solid body instruments. These were originally marketed as Electric Hawaiian guitars. There are two types: one that sits on the musician's lap and a second version that has legs and was called a console version, but did not include pedals or knee levers. Electric lap steels are typically made with six to ten strings