Similar to the MKV file extension, WEBM is a file format developed by a number of parties, including Google. Launched in 2010, it is open source format designed to deliver video through the web. It can be used for a variety of types of video, from video calls to high definition movies. WebM is growing, and by using the HTML5 version of YouTube, it is possible to watch video encoded in WebM.
WebM benefits from being designed for use on the modern web, rather than for local use. This means the format is specifically designed for the wide range of devices that are used to access the web, from Smart Phones to Powerful PCs. The video element of the file is encoded using VP8 video codec and the audio element of the file is encoded using the Vorbis audio codec.
Google Chrome Mozilla Firefox VLC Media Player
Google (Previously developed by On2, Xiph, and Matroska)
MP3 is a digital music format which allows CD tracks to be reduced to around a tenth of their normal size without a significant loss of quality. MP3 gets rid of a lot of the information recorded in a song that our ears are not able to hear and then uses complex algorithms to reduce the file size. This then enables you to get hundreds of songs on to a CD and it also has opened up a new market over the internet - the download market as download times have been significantly reduced.
The MP3 format is a lossy format. That means that an MP3 file does not contain 100% of the original audio information. Instead, MP3 files use perceptual coding. In other words, that means it removes the information that your ear doesn't notice thereby making the file smaller. The reason lossy formats are used over raw is that raw audio files are too large to travel over the internet at any great speed. By using lossy formats it enables even dial up users to download mp3 files at a reasonable speed. Raw file formats generally require 176,000 bytes per second compared to a lossy format which requires 17,600. The difference is massive and so are the download times.