How do I add ffmpeg to my PATH environment variable?

The process varies by OS. On Linux/macOS, you can modify your `.bashrc`, `.zshrc`, or similar shell configuration file. Add a line like `export PATH=$PATH:/path/to/ffmpeg`. On Windows, search for 'environment variables' in the Start menu, edit the 'Path' variable, and add the ffmpeg directory. Remember to restart your terminal after making changes.