Audacity is a free and lightweight audio recorder and editor tool you can use on Mac, Windows, and Linux, too. It's available in many languages and is entirely audio-focused, used for recording live audio, external audio through a microphone, and system audio, too. It's also an impressive editor tool for editing your audio recordings and works with many different sound file formats, but you will have to download some extra software to get it working with your system audio.
To see the detailed review of Audacity, follow the link below:
Read the review by PCWorld
Best for: users who want to make and edit high-quality system sound recordings