(API, or "application programming iNTerface") The iNTerface (calling conveNTions) by which an {application program} accesses {operating system} and other services. An API is defined at source code level and provides a level of abstraction between the application and the kernel (or other privileged utilities) to ensure the portability of the code. An API can also provide an iNTerface between a {high level language} and lower level utilities and services which were written without consideration for the calling conveNTions supported by compiled languages. In this case, the API' s main task may be the translation of parameter lists from one format to another and the iNTerpretation of call-by-value and call-by-reference argumeNTs in one or both directions. (1995-02-15)