mythtv-setup is a configuration utility for configuring mythtv-backend. It is the first program to start with your overall MythTV setup. As of version 0.20.2, it comprises of 4 sections: 1. General 2. Capture cards 3. Video sources 4. Input connections 5. Channel Editor
All these sections are briefly explained in [Configuring MythTV] section of Robert Kulagowski. This wiki page will explain in-depth all options and provide useful screenshots for new users.
Video capture card configuration.
TV listing service configuration.
Associate video sources with capture cards.
File storage configuration.