HTTP Live Streaming (HLS)

This HTTP-based media streaming protocol enables live streaming of audio or video over the internet for appropriate Apple products. It is a part of iOS, OS X, QuickTime and Safari and works by dividing the required source media into small chunks of around two seconds, then offering media files in several levels of H.264 video and MP3 or HE-AAC audio compression, providing from low to high bit-rate (and quality) delivered in an MPEG-2 Transport Stream. The data delivery system is adaptive to allow for variations of available data speeds, with the receiving end able to choose the highest bit-rate files it can receive fast enough to maintain live operation.

See also: Buffering, Adaptive bit-rate streaming