ABSTRACT
The importance of language in normal human thinking is undoubted. The communicative aspect of language is hardly of less importance. The area of mechanical translation is one in which the computer processes language symbols, and occasionally computer-assisted instruction also involves the manipulation of natural language. List-processing languages have been used especially in programs dealing with natural language. The operations usually allowed for in list-processing languages include: comparing symbols, locating a symbol on a list, deleting a symbol from a list, combining two lists into one, and adding a symbol at the end of a list. Question-answering, which is hardly used at all yet in industry or elsewhere, is an extension of information retrieval in the sense that the aim of a question-answering program is to retrieve information requested in natural language. Question-answering is really only one possible form of natural language interaction with a computer.
