IEC62766-2-2:2016 specifies media formats for adaptive unicast content streaming over HTTP.Two HTTP adaptive streaming formats are specified. The first is based entirely on MPEG DASH. The second is the OIPF “ HTTP adaptive streaming?? (HAS) format, which is based upon 3GPP’s release 9 adaptive HTTP streaming (AHS) format, with some profiling and extensions to add the features of media components and support for MPEG-2 transport stream content segment format. The latter format was specified before MPEG DASH had been published. It is retained due to usage in some legacy applications.