Audacity

From ArtSoftware

Audacity is a free, open source, cross platform digital audio editor. The source code for Audacity is released under the GNU General Public License. The graphical user interface for the editor has been produced using the wxWidgets library.

Audacity was created by Dominic Mazzoni of Google, while he was a graduate student at Carnegie-Mellon University. Dominic Mazzoni is still the main developer and maintainer of Audacity, with help from many others around the world.

Audacity is extremely popular in the podcasting world due to its wide availability, multiplatform support, and the fact that it is free.

Features

Some of Audacity's features include:

Importing and exporting WAV, MP3 (via the LAME MP3 Encoder), Ogg Vorbis, and other file formats
Recording and playing sounds
Editing via Cut, Copy, Paste (with unlimited Undo)
Multi-track mixing
Digital effects and effect plug-ins. Additional effects can be written with the Nyquist programming language
Amplitude envelope editing
Noise removal
Support for multichannel modes with sampling rates up to 100 kHz with 24 bits per sample
The ability to make precise adjustments to the audio's speed, while maintaining pitch, in order to synchronize it with video, run for the right length of time, etc. Unlike many other programs, Audacity has very few audible artifacts (doubling, or chorus type effects) when lengthening or shortening a file.
Large array of plug-ins available