Audacity

Audacity is a free, easy-to-use and multilingual audio editor and recorder. Basic features, as listed on their website, include:

• Record live audio.
• Record computer playback on any Windows Vista or later machine.
• Convert tapes and records into digital recordings or CDs.
• Edit WAV, AIFF, FLAC, MP2, MP3 or Ogg Vorbis sound files.
• Cut, copy, splice or mix sounds together.
• Change the speed or pitch of a recording.