Free Software that I rely on. One per day.
Day 6:
Audacity
Another old one! I think I've been using Audacity for about 25 years, now.
It is a "destructive audio editor", which means it is kind of the audio equivalent to a bitmap editor in graphics -- you are actually changing the values of the samples in the recording when you make changes, rather than applying filters on top of them as non-destructive editors do.
This makes Audacity particularly good at constructing sound effects from recorded sources.
I do most of my audio processing in Audacity, but even if I do involve a non-destructive "DAW" platform, I would probably continue to use Audacity for creating effects and recording voices.
It is an excellent tool for recording audio directly or reviewing and selecting audio from field recordings.
