THERE WAS A time when a radio program required an actual radio station. Podcasting changed that. It is now possible to transmit a talk show, a documentary, or an audio play without dealing with anyone licensed to broadcast on the AM or FM bands.
Needless to say, this costs a lot less to operate than it did the old way. And with less money on the line, your audience doesn't need to be as big for your show to be profitable--if profits even matter to you in the first place. (There are podcasters who run their programs as a hobby or a community service, even if they aren't getting any subsidies from the Corporation for Public Broadcasting.) The opportunity costs are different, too. Before, your show didn't simply need to turn a profit; it needed to be more profitable than anything else that might occupy your spot on the schedule. Not anymore.
With broadcasters liberated from such costs and constraints, we've seen a flowering of creativity and variety. There is a podcast for every niche, from surreal horror-comedy (Welcome to Night Vale) to the history of country music (Cocaine and Rhinestones).
It took a while to get here. When Dave Winer coined the term pod-castingin 2004, the medium itself was a small niche. In theory, "pod" stood for "personal option digital" (or sometimes "personal on demand"). But the aim was to evoke the iPods that people could use to listen to the programs. Winer made up the acronym because he didn't want to tie the idea too closely to one...