A content-evaluating mode of computer-aided instruction

In the literature describing the languages and systems available for writing teaching programs, two main lines of development have been apparent [1]. At one pole is the system using the linguistic mode. Here, the student interacts "verbally" with the computer, in the sense that messages are sent to the computer by him and are then interpreted "verbally" by the machine. By this we mean that the steps the computer takes assume that the words received need not be decoded further; that is, the words themselves make up the target language.