IBM Advanced Program-to-Program Communication

In computing, Advanced Program to Program Communication or APPC is a protocol which computer programs can use to communicate over a network. APPC is at the application layer in the OSI model, it enables communications between programs on different computers, from portables and workstations to midrange and host computers. APPC was developed as a component of IBM's Systems Network Architecture or SNA. Several APIs were developed for programming languages such as COBOL or REXX.