A dumb terminal in computing refers to a computer terminal that has limited functionality relative to other types of "smart" computer terminals. • The specific meaning of the term can vary a bit depending on the context in which it is used.
In the context of traditional computer terminals that communicate over a serial RS-232 connection, dumb terminals are those that do not have the ability to process special escape sequences that perform functions such as clearing a line, clearing the screen, or control cursor position. • In this context dumb terminals are sometimes dubbed glass teletypes, for they essentially have the same limited functionality as does a teletype. • This type of dumb terminal is still supported on modern Unix-like systems by setting the environment variableTERM to dumb. Smart or intelligent terminals are those that have the ability to process the special escape sequences.
In the broader context that includes all forms of keyboard/screen computer communication devices, including personal computers, diskless workstations, network computers, thin clients, and X Terminals, the term dumb terminal is sometimes used to refer to any type of traditional computer terminal that communicates serially over a RS-232 connection.