The programming language PL/T.

Despite the dramatic reduction in the cost of computation, mass storage and semi-conducter storage, the advance of computer aided learning in our education centers uill be sloued by the unavailability of software (courseusre). We can expect courseuare to be unavailable in the near term because 1) softuare development costs are rising, 2) much of the available courseuare is tightly coupled to a single machine, and 3) much of the available courseuare has been developed by novice programmers and is neither transportable nor easily maintained. PL/T (Programming Language for Teaching) delivers a notation in uhich courseuare can be expressed in a concise, natural way. It is easy to use, yet pouerful enough to configure very complex programs. The PL/T system includes a one-pass, recursive descent compiler uritten in PASCAL. PL/T source lessons are translated into an intermediate PL/T "machine code" uhich is interpreted by another PASCAL program. The use of PASCAL increases the portability of PL/T courseuare. Additionally, PL/T includes primitives for structured programming uhich facilitate construction of very readable, very maintainable lessons.