The bewildering number of available terminals which are offered to CAI users presents a rather formidable problem of which one to choose. This article surveys what appear to be evolving standards for terminals. The usefulness of these terminals for CAI purposes is discussed, together with the best known prototype exhibiting the particular feature. Based on different technological requirements, terminals may be classified into the following five categories: (1) typing terminals, capable of displaying alphameric information only, with hardware character generators; (2) Cathode Ray Tube (CRT) terminals, capable of displaying alphameric information only; (3) CRT terminals with programmable character generators, capable of displaying pre-stored graphic information; (4) CRT terminals with the ability of addressing each point on the screen, capable of displaying generated graphic information; and (5) video terminals capable of displaying moving pictures in addition to full graphic capability. The characteristic technology, and advantages and disadvantages for each of these five classes of terminals is discussed. (Author/VT)