MP3:
MPEG-1 or MPEG-2 Audio Layer III, more commonly referred to as MP3, is a patented digital audio encoding format using a form of lossy data compression.
It is a common audio format for consumer audio storage, as well as a de facto standard of digital audio compression for the transfer and playback of music on digital audio players.
The use in MP3 of a lossy compression algorithm is designed to greatly reduce the amount of data required to represent the audio recording and still sound like a faithful reproduction of the original uncompressed audio for most listeners. An MP3 file that is created using the setting of 128 kbit/s will result in a file that is about 1/11 the size of the CD file created from the original audio source.
An MP3 file can also be constructed at higher or lower bit rates, with higher or lower resulting quality.
WMA:
Developed by Microsoft, WMA is an audio encoding/decoding system enabling compression of the data on a CD to up to 1/20 its original volume.
Data encoding is performed with Windows Media Player 7, a standard feature of Windows. You can download Windows Media Player from Microsoft's free Download Service.
MicrosoftR and WindowsR are registered trademarks of Microsoft Corporation in the United States and/or other countries.
Windows(R) is the official name for the MicrosoftR WindowsR Operating System.
WMA (Windows Media Audio) is the new CODEC for audio developed by Microsoft Corporation in the United States.
AAC:
The AAC (Advanced Audio Coding) audio codec achieves audio encoding with a much higher compression efficiency than previous formats such as MP3.
KENWOOD H/U featuring AAC can reproduce MPEG-4 format .m4a files that are compressed by using AAC-LC, as well as the files recorded in the MP3 and WMA (Windows Media Audio) music compression formats.
The H/U can display the title information according to the WMA tag and MP3 ID tag showing titles and artist, and is also compatible with the long name files of Joliet and Romeo.