Audacity

Audacity is free, open source software for recording and editing sounds. It is available for Mac OS X, Microsoft Windows, GNU/Linux, and other operating systems. It is a very useful audio editor that can edit OGG, WAV, AIFF, AU and MP3 files, as well as importing RAW files.

It uses LAPSDA plugins, and on Windows can use VST effects with an extra enabler. Audacity can be found useful in many different applications in the audio field.

At current, Audacity is currently available as a stable version 1.2.6 and a beta version 1.3.2, which has a host of new useful features.