Audacity is a popular free digital audio editor and recorder. This software was created by Dominic Mazzoni and he still plays an active part in its development. As of May 2009 it has been downloaded a total of 59 million times. It is free software and a lot of people contribute to this project from around the world. There are a lot of audio files that are supported by Audacity. Some major ones are WAV, MP3, AIFF, Ogg Vorbis, FLAC and others. You can also add digital effects through plug-ins and remove noise from the audio files. Audacity is also available in many languages. To download the free software just go to their website.