Podcasts are small audio/video files, usually saved as an MP3/4 file format that can be played with a media player either on a computer with a program such as Winamp, VLC Media Player, RealPlayer or Windows Media Player. They can also be played on a dedicated MP3 device such as Zune, iPod etc.
However, most modern cell phones also have the ability to download music or any media file, either through wi-fi or a mobile data service such 3G or EDGE. This negates the need to travel with two devices, since the mobile phone can act as your media player/iPod.
This ability, presents the opportunity to download, news or other educational or informative media on your phone for playback when you have time on your hands, in the line at the bank or utility company, on the bus/train ride to work for example.
I routinely download a bunch of podcasts using my wi-fi connection in the morning, while fixing breakfast, from various sites and then play them later in the day. Some media players on mobile devices allow for you to subscribe to various feeds and will then download the latest podcast as and when it becomes available.
Additionally, the popular browser Opera, which can be downloaded for mobile phones has the ability to subscribe to RSS feeds and download podcasts.
There is a host of different podcasts to suit every taste or preference. For example, the technology web site CNET, and National Public Radio – NPR and the BBC are all very good sources.