Audio Stream Input/Output: An ASIO audio device driver interface.

ASIO is a protocol established by Steinberg of Germany as an application API for audio signal input/output, and is the de facto industry standard. Mac OS X's Core Audio is considered equivalent technology. There are sound drivers in Windows and MAC operating systems, but ASIO provides lower delay, higher synchronicity and higher throughput. The sound drivers provided with conventional operating systems are not designed for multi-channel input (over two channels), so multi-channel inputs for channels over two are required.