A typewriter is a mechanical or electromechanical machine for typing characters. Typically, a typewriter has an array of keys, and each one causes a different single character to be produced on paper by striking an inked ribbon selectively against the paper with a type element. At the end of the nineteenth century, the term 'typewriter' was also applied to a person who used such a device.
Mechanical desktop typewriters, such as this Underwood Typewriter, were long-time standards in government agencies, newsrooms, and offices.
Peter Mitterhofer's typewriter prototype (1864)
The 1969 Olivetti Valentine typewriter, featured in the permanent collections of the Metropolitan Museum of Art, Museum of Modern Art, and Cooper Hewitt, Smithsonian Design Museum in New York; London's Design Museum and Victoria and Albert Museum.
An Elliott-Fisher book typewriter on display at the Historic Archive and Museum of Mining in Pachuca, Mexico
In engineering, electromechanics combines processes and procedures drawn from electrical engineering and mechanical engineering. Electromechanics focuses on the interaction of electrical and mechanical systems as a whole and how the two systems interact with each other. This process is especially prominent in systems such as those of DC or AC rotating electrical machines which can be designed and operated to generate power from a mechanical process (generator) or used to power a mechanical effect (motor). Electrical engineering in this context also encompasses electronics engineering.
A relay is a common electro-mechanical device.