Audacity - Audacity is a free and open-source audio production software suite that includes a surprising array of editing tools and recording systems.
Oceanaudio - Ocenaudio is a cross-platform, easy to use, fast and functional audio editor.
GarageBand - GarageBand is a fully equipped music creation studio for Mac
GoldWave - GoldWave. Digital Audio Editing Software. Record • Restore • Convert • Analyze. Fully loaded to do everything from the simplest recording and editing to the most sophisticated audio processing, restoration, enhancements, analysis, and conversions.
Adobe Audition - Mix, edit, and create audio content in Adobe Audition CC with a comprehensive toolset that includes multitrack, waveform, and spectral display.
AudioMass - A full-featured web based audio editor 🎶