What is a podcast?

I wanted to talk a bit about podcasts. I've been thinking about it and I realize that not everyone knows what a podcast is the same way I had to ask my children repeatedly what Twitch was... There are so many different types of technology these days! A podcast is like listening to an old fashioned radio show. It's completely free (just like public radio) but there are many, many kinds of programs. When I discovered podcasts my life literally changed... and my insomnia wasn't so bad. ;-)