ISS (Integrated sound system) has been implemented into SkyOS. The ISS is a very well integrated sound system which makes it very easy to access the audio multimedia services of SkyOS, though providing a very powerful interface. The simplest way to play an audio file in an application is by just calling the ISS_PlayAudioFile function with a filename. On the other side you can create really complex audio applications by using the various functions provided by ISS. For example you can create two audio streams, one stereo, one 5.1 DolbyDigital, connecting an echo filter to the second, associating the 5.1 stream with a SB Audigy live and the stereo stream with a basic stereo soundcard and apply various software digital filters to individual streams.