Most teens consider MP3 as the “in-thing” to have. It is the equivalent of the walkman from way back. It stores digital music compressed to a much smaller size than a compact disc but the music is of the same quality. There is no need for storage devices to be slotted in to the unit to play music. It has similar components as the computer – data port, memory, microprocessor, digital signal processor, playback devices, audio port, amplifier and power supply. They come with software programs for managing files and downloading music. The unit is run either by batteries or by plugging into an AC adaptor.

It is often said that the MP3 was invented by Karlheinz Brandenburg, but he doesn't want to take the credit for it. He attributes its development to a host of core developers with many others contributing. While he was trying to discover the discipline of how people understand and see music, he was tasked to reproduce the song of a folk rock singer without the background noise. So in collaboration with other MP3 developers they were able to refine the technology up to a point that the song sounded just like the original. This served as the break they needed and further research had the MP3 establish its niche in the industry.

Advanced Streaming Format is Microsoft's own digital audio/video container format and is part of the Windows media framework. It can store compressed audio and video content that can be played back using a media player equipped with the proper codec. This extensible file format is designed to keep coordinated multimedia data and supports advanced multimedia capabilities that include extensible media types, component download, and scalable media. Windows Media Video (WMV) and Windows Media Audio (WMA) are the most common files found in an ASF file and can use the ASF extension. These files can also include the metadata for the audio/video file similar to ID3 tags for MP3 files.

Advanced Audio Coding or AAC, a standardized glossy compression and encoding format for digital audio, was designed to resolve the major performance flaws found in the MP3 format. Its audio encoding provides more efficient compression than the older formats but does not reduce its quality and can rival that of an uncompressed audio CD. AAC makes use of two main coding strategies to significantly lessen the amount of data needed to stand for high-quality digital audio: discarding the signal components that are perceived to be immaterial; and eliminating the unessential in the coded audio, at the same time adding internal error correction codes.

There are just a few proposed standards for encoding to gain and MP3 file, listeners may want to hear the music file like an original soundtrack, but this does not conclude that they want to use volume control for each track being played, but notice the music played on an original compact disc, the volume was intentionally set by a professional mastering engineer, for each track has equal volume, compact discs & other different sources are digitally mastered and recorded at different volumes, so when playing tracks one after the another, it may be convenient to set volume information on the tag being used so when you play it again, the volume dynamically adjusts itself.