As you can see in the screenshot alongside, the interface of Audacity is not very overwhelming. One can easily chop and

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merge audio files using simple 'Cut','Copy','Delete' and 'Paste' commands. Another fantastic and very useful feature (especially if you bungle up) is the unlimited 'Undo' and 'Redo' feature. Its one feature which I particularly love!
Like proprietary software, Audacity too offers the capability to edit an unlimited number of tracks. There are simple tools for audio mixing, fading and increasing and decreasing volume very smoothly.