Micros Systems Workstation 4 Setup Manual page 91

WS4 Glossary
API
Abbreviation for Application Programming Interface (API). The WS4
API is a direct descendant of the PCWS hardware API that resides
between an application and the hardware, providing a set of hardware
services that the application programmer can call upon to access the
POS features of the Workstation 4.
For example, to open a cash drawer, the programmer calls an API
function. The API determines which system board is installed and
selects the appropriate register and bit in the CPLD to open the
drawer. Changes to a register port address, or a new version of the
system board is handled by the API and thus are transparent to the
programmer.
Glossary
Glossary-1