Audacity is the venerable open-source audio editor that has been around since 1999. It records from microphone or line-in, imports and exports the usual formats (WAV, AIFF, MP3, FLAC, Opus), edits across unlimited tracks, and ships a broad set of effects, generators, and analysis tools — plus support for LADSPA, LV2, VST3, and Audio Unit plug-ins. Built-in noise reduction, normalization, click removal, and spectral editing handle most podcast and music post-production needs.

It's available for Windows, macOS, and Linux as a native download, with active development now stewarded by Muse Group (also Ultimate Guitar, MuseScore). The project is GPL-licensed, free in every meaningful sense, and remains the default "open it, do the thing, save" audio editor for podcasters, archivists, and anyone who just needs to trim and clean a recording without learning a DAW.