M4A files are a type of audio file developed and popularised by Apple. Since 2007, music purchased through the iTunes store has been in m4a format, therefore accounting for over 15 billions files worldwide. MP4 and M4A files are often confused, and the two are quite similar, being both based on the MPEG-4 codec. However, M4A is a file comprising solely of audio, whereas MP4 may also contain video.
M4A files are superior to MP3 in terms of the scale of compression and audio quality. The M4A file uses Apple's codec and resides within the MPEG-4 container. The main benefit of M4A is that files are compressed but are lossless. This means they can be decoded back to the original quality they were at the point of compression. Another benefit of M4A files are that do not carry any Digital Rights Management (DRM) protection associated with other files meaning they are less restricted.
Associated programs
Apple QuickTime Player Apple iTunes Microsoft Windows Media Player
Free Lossless Audio Codec, or FLAC for short, is an audio compression technique. It is a lossless compression type meaning that the compression takes place without data being discarded. FLAC is an open source codec. FLAC is a format that is recommended to those backing up a CD collection because the sound quality will remain high, whereas MP3 compression will result in a deterioration compared to the original.
Using FLAC to compress an audio file to approximately 50% of its original size. The main benefits of a FLAC file in addition to it being lossless is that it can be used for streaming, and decoding is fast, allowing for real time decoding to take place. A FLAC file also contains several data integrity checks in the header file. The metadata associated with the audio has been future proofed also to allow new fields to be defined without impacting existing decoders.
