They are easily listening without many complex concepts as can be found in lectures of tertiary educational institutes, but that's not the goal anyways. They are great for getting a feeling about topics while running or sitting on the train. Perfect balance. Thanks for making it and keeping it free in the spirit of free knowledge !

This is one of the best, most highly produced (apparently) shows out there – good content, and great presentation, makes it easy, instructive and even enjoyable to listen.