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What is an MP3?

close up image of a pair of headphones

MP3 is a digital music format for creating high-quality sound files. It has transformed the way people buy and listen to music.

WebWise Team | 10th October 2012

The great attraction of the MP3 format is its ability to compress files, making it a convenient, versatile and very popular way of storing music.

How it works

MP3 achieves its powerful compression by stripping out a lot of the sounds in a song which our ears cannot hear, and using complex mathematical algorithms to reduce file sizes further. The result is that MP3 files are around 11 times smaller than uncompressed music tracks.

Thanks to these impressive rates of compression a typical music track is reduced from about 50MB (megabytes) to around 4MB. You can fit more than 100 MP3 tracks on a typical audio CD instead of around 16 tracks in the old format (called .WAV) still used on commercial music CDs.

What are the benefits?

Because of the small file size you can easily download and email MP3s. There are numerous programs for playing MP3s available, such as Windows’ Media Player, Real Player, iTunes or WinAmp.

Although all of these programs will play your MP3 tracks, if you buy music through them they will download tracks in another format. It is possible to buy special software to convert to and from MP3. But to save yourself the hassle, it is worth thinking about what you will use to play the music before you download it.

Numerous websites offer legal MP3 downloads for a small fee, typically less than £1 per track.

Many people upload (‘rip’) their CD collection to their computer. Once stored on your hard drive, you can play your music through the speakers on your computer or through headphones. You can also create your own compilation albums and playlists.

When you rip from a CD to your computer’s hard drive, you will be able to choose the levels of compression. The higher you set the compression rate (typically between 48 and 192 Kbps) the smaller the file will be, but with a resulting loss in audio quality.

You can copy MP3 files onto a portable MP3 player - or in the case of iTunes, an iPod or other Apple device. Portable radio/CD players now have the capability to play MP3s too. Another option is copying (‘burning’) music downloads from your computer to a blank CD.

Possible misuse

The sheer success of MP3s makes them prone to misuse.

Piracy – the illegal downloading and sharing of music - has become a big problem for the music industry, and the subject of high-profile legal actions. While it may be tempting to swap music files online, it remains a breach of copyright law.


The WebWise 'W'

WebWise Team

WebWise was first launched in 1998 and since then has helped people of all ages to learn about and love the internet.

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