The full term for MP3 is MPEG-2 Audio Layer III. As the name suggests MP3 players are capable of playing only the audios i.e. the songs and voice recordings. The MP3 players use a compression algorithm that is designed to reduce the data of the audio. This results in a reduction of the file size without hampering with the quality of the audio any bit.
The term MP4 player is used to refer any of the several media players that are portable and can support certain formats. Quite interestingly, none of the MP4 players support the .mp4 format. While MP3 player plays only the audio, the MP4 players would play a number of video formats.
iPod is a range of media players that are portable and are created by Apple Inc. The iPods have made it possible to store a large number of songs, videos, movies and even games. Over the past few years various models of iPod have been developed as well as discontinued.
