First launched: 1996 (Patent filed in the US)

Uses: Audio storage as a compressed file on computers

Fun fact: auditory masking, one of the principles behind MP3, was written about as early as 1894.

Reference: HowStuffWorks.

The MP3 was the earliest widely used lossy compression format. But what is ‘lossy’ compression?

When CDs started hitting the market, the computer landscape was very different. The typical size of a hard-drive (if you had one) was around 10 mb - for context, the average size of a song on a CD is around 32mb. But as drive sizes and personal computers became bigger and more commonplace, ‘ripping’ a CD became very popular and very dangerous for record labels.

Despite the ability to rip CDs, the average user’s hard drive would still be far too small to store the files in their uncompressed (WAV) format - this is where the idea of compression comes in.

Lossy audio compression operates on the basis of three facts about human hearing:

• the ear cannot hear past certain frequencies
• the ear hears some sounds better than others
• when two sounds play simultaneously, we can only hear the louder of the two (auditory masking)

MP3 uses factors like these to partially discard parts of an audio file, leaving you with a file that is up to 75%-95% smaller. This allowed people to store hundreds of songs on their computers, and thus allowed them to share them easily.

With the internet exponentially growing with each year, software to connect users from all over the world began popping up. Chat clients, forums - and, of course, sharing music online. Instead of simply showing a song to your friend while you were in the same room together, you could send them the file directly: something that MP3’s heavy compression made practical even in the era of painfully slow dialup internet.

Napster has attained infamy for being the first program of its kind to really explode into the public consciousness. It was a P2P (Peer to Peer) file sharing service which allowed any user to easily share and download music files from other users: at the height of its popularity Napster had 80 million users. It was so popular among college students that dormitory internet became overloaded, with over 60% of the traffic consisting of MP3 file transfers.

Eventually a wave of lawsuits would shut down the service in 2001, but not before the concept of free-to-access music was firmly planted in the public consciousness. Today, torrent sites and P2P clients like SoulSeek provide the same functionality, but even better with an endless stream of lossless audio, video, and software.

One of Napster’s direct successors gained a more nefarious reputation, however. LimeWire was much like Napster in that it focused on ease of use and free media: it was designed to share video and software as well. By 2005 it had 1.7 million users. Its biggest flaw was the complete lack of content filtering and file verification: meaning many of the files were mislabeled, duds, or viruses.

The first portable MP3 player was released in 1997, by a company called Saehan Information Systems. It used flash based memory with storage options of 32MB and 64MB - 6 or 12 songs. By 2001, there were 6 MP3 players on the market, all of which were either too large to be portable or small and lacking in functionality. In classic Apple fashion, they were not the first to attempt the idea of a portable MP3 player, but they did it well.

Released in 2001, the 1st generation iPod was developed in less than a year and debuted with the tagline “a thousand songs in your pocket” - it was roughly the size of a deck of cards, but still held a 5gb spinning hard drive inside. The ‘silhouette’ ad campaign became a driving force behind establishing the product as a must-have, and the iPod (and its many sub-variants) became a defining device of the 2000s-2010s.

In 2003, Apple once again sought to capitalize on the downloadable music market; seeing the rampant piracy of copyrighted music across the internet and the failure of Sony’s attempts in making a digital storefront, Apple negotiated a deal with the five major record labels to create the iTunes Store: a way to easily and legally purchase MP3 files for personal use. By this point in time, CD-Rs (recordable CDs) and their compatible drives had gotten cheap enough for the average user to own, and a common use of MP3 files was to ‘burn’ them to these discs.

Apple appealed to this crowd of users in their original press release:

The iTunes Music Store offers groundbreaking personal use rights, including burning songs onto an unlimited number of CDs for personal use, listening to songs on an unlimited number of iPods, playing songs on up to three Macintosh® computers, and using songs in any application on the Mac®, including iPhoto™, iMovie™ and iDVD™.Source

The risk associated with free services like LimeWire only served to draw more customers to the iTunes Store, and it proved to be yet another hit for Apple. Their attractive pricing model (99 cents per song) and ease of use with the ever-popular iPod was hard to beat, and by 2010 it was the largest music vendor in the world.

MP3 was not without flaws. While it aimed to be ‘close’ to CD-quality audio, this highly depended upon the bitrate of the file; 128kbps was the most common type since it was the most space-efficient, but sonically it was the most compromised. The fidelity of a track is more obviously noticed in genres like classical, which is why many classical listeners opted to stick with CDs.

Other formats such as AAC (Advanced Audio Coding) have attempted to replace MP3 as a more efficient, better sounding alternative. For people looking to rip audio from something like a YouTube video, however, the top search result will still be some variant of “YouTube to MP3”. The irony is that YouTube itself uses the AAC format.

The MP3: A History Of Innovation And Betrayal

MP3, AAC, WAV, FLAC: all the audio file formats explained

How MP3 Files Work

How Well Can You Hear Audio Quality?