Digital Music

• The iPod is the ubiquitous Apple digital music player (DMP). Digital music players store music in digital files (binary code) and then use a DAC (digital-to-analog) converter to turn the digital file composed of 0's and 1's into an analog signal that can be played through speakers or headphones. Generally, digital music has better clarity and can be compressed to fit a large amount of music onto digital storage media such as hard disks and memory cards. In addition, digital music players also contain an embedded processor to convert the music files using codecs, the technologies that compress and decompress the audio signals.
  
  

Compressing Files

• IPods utilize a number of codecs to playback multiple formats of digital music files including the popular MP3 format. MP3 stands for MPEG audio layer III, a method for compressing audio files. This standard for audio compression became popular because it is capable of at least 10:1 compression with little noticeable loss of quality. Compression refers to the size of the file. An uncompressed audio file that contains 50 MB worth of data can be compressed using MP3 compression technology to a 5 MB file and still retain high sound fidelity. IPods also support the formats AAC, Audible, WAV, AIFF and Apple Lossless.
  
  

Playback

• The iPod is more complicated than its sleek design suggests. It contains many technologies and features that allow it to perform its basic function of storing and playing music. One technology vital to DM players is solid-state memory. This refers to the hard disk or flash memory card that holds the files in memory, as opposed to CD players or tape players that only play separate disks and tapes which hold the music. IPods use small hard disks to store files, typically in the 80 to 160 GB range. IPods also contain some programming that allows you to organize and catalog the music into playlists as well as the ability to easily integrate with your computer to transfer files back and forth. Most iPods also contain an LCD screen for viewing music files and a touch wheel for navigating and controlling playback. Lastly, iPods contain a power source and an audio port for headphones or speakers that allow you to enjoy your music