AAC is NOT an Apple format. Advance Audio Codec (AAC), MPEG-4 (MP4)
MPEG-4 was defined by the Moving Picture Experts Group (MPEG), the working group within the International Organization for Standardization (ISO) that specified the widely adopted, Emmy Award-winning standards known as MPEG-1 and MPEG-2. Hundreds of researchers around the world contributed to MPEG-4, which was finalized in 1998 and became an international standard in 2000.
3GP is also NOT an Apple format. 3GPP and 3GPP2 are the worldwide standards for the creation, delivery and playback of multimedia over 3rd generation, high-speed wireless networks. Defined by the 3rd Generation Partnership Project and 3rd Generation Partnership Project 2 respectively, these standards seek to provide uniform delivery of rich multimedia over newly evolved, broadband mobile networks (3rd generation networks) to the latest multimedia-enabled cell phones
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