PL/C is a computer programming language developed at Cornell University with the specific goal of being used for teaching programming. It is based on IBM's PL/I language, and was designed in the early 1970s. Cornell also developed a compiler for the language that was based on its earlier CUPL compiler, and it was widely used in college-level programming courses. The two researchers and academic teachers who designed PL/C were Richard W. Conway and Thomas R. Wilcox. They submitted the famous article "Design and implementation of a diagnostic compiler for PL/I" published in the Communications of ACM in March 1973, pages 169-179. PL/C eliminated some of the more complex features of PL/I, and added extensive debugging and error recovery facilities.PL/C is a subset of PL/I. A program that runs