The Underwood typewriter was the forerunner of the modern typewriter. It allowed the typist to see what they were typing. By 1939 Underwood had produced five million machines.

From 1874 the Underwood family made typewriter ribbons and carbon paper, and were among a number of firms who produced these goods for Remington. When Remington decided to start producing ribbons themselves, the Underwoods apparently decided to get into the business of manufacturing typewriters.

The original Underwood typewriter was invented by German-American Franz X. Wagner, who showed it to entrepreneur John T. Underwood. Underwood supported Wagner and bought the company, recognising the importance of the machine. Underwood No. 1 and No. 2s, made between 1896 and 1900, had "Wagner Typewriter Co." printed on the back.

Underwood started adding addition and subtraction devices to their typewriters in about 1910.

Underwood was bought by Olivetti in 1959.