It is most commonly used to store digital video and digital audio streams, especially those defined by MPEG, but can also be used to store other data such as subtitles and still images. MPEG-4 Part 14 or MP4, formally ISO/IEC 14496-14:2003, is a multimedia container format standard specified as a part of MPEG-4.Output formats supported by Gihosoft Free Video Converter are MP4, AVI, WMV, MKV, MOV, FLV, SWF, WEBM, ASF, 3GP.