Tab keyThe tab key (abbreviation of tabulator key or tabular key) on a keyboard is used to advance the cursor to the next tab stop. The word tab derives from the word tabulate, which means "to arrange data in a tabular, or table, form." When a person wanted to type a table (of numbers or text) on a typewriter, there was a lot of time-consuming and repetitive use of the space bar and backspace key. To simplify this, a horizontal bar was placed in the mechanism called the tabulator rack.
TeleprinterA teleprinter (teletypewriter, teletype or TTY) is an electromechanical device that can be used to send and receive typed messages through various communications channels, in both point-to-point and point-to-multipoint configurations. Initially they were used in telegraphy, which developed in the late 1830s and 1840s as the first use of electrical engineering, though teleprinters were not used for telegraphy until 1887 at the earliest.