Great question! Some of our programmers (and other folks) put their shows on Soundcloud, or Archive.org, or other places. Which is a great way to get your work online so people can find it, but that’s not actually “podcasting”.
The good people at International Podcast Day define podcasting succinctly here. It’s worth a read. The key bit is the last part:
…what truly makes a podcast unique, and what gives a podcast its “casting” ability, is how it is able to immediately deliver itself to multiple podcast distibution points (such as iTunes and Sticher Radio) or podcatcher applications through a process of syndication known as RSS (Real Simple Syndication)… subscribers are automatically notified without having to constantly check back with the podcast’s website to see if a new show has been produced.
In a nutshell, a podcast is an audio file on the Internet, distributed automatically to subscribers.
The magic is that listeners don’t have to take any action to find and listen to episodes — they are delivered right to their device, automatically.
Having audio delivered right to a listener means much higher retention than you get with traditional audio files on the Internet — or even radio. Rather than telling somebody “you have to visit my website every week, go to this page, and download a file,” or “you have to tune into this frequency every week, at a certain time on a certain day,” you’re delivering the show directly to them.
In other words, if it’s not available on podcast apps (Apple Podcasts, Stitcher, Google Play, and other apps like Overcast, PodBean, etc…) it’s not a podcast.
The magic is in the apps, and in that automatic download right to listeners’ devices — and ears.