Which one is not included in the new inventions of the 21st century?
MP3 was introduced as an audio coding standard in 1994. It was based on several audio data compression techniques, including the modified discrete cosine transform (MDCT), FFT and psychoacoustic methods. The first portable MP3 player was launched in 1997 by Saehan Information Systems, which sold its “MPMan F10" player in parts of Asia in spring 1998. In mid-1998, the South Korean company licensed the players for North American distribution to Eiger Labs, which rebranded them as the EigerMan F10 and F20. The flash-based players were available in 32 MB or 64 MB (6 or 12 songs) storage capacity and had a LCD screen to tell the user the song currently playing.
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