During the past few years, it has been made possible to the radio on different devices such as the internet, mobile phone, tablets and also the tv.
Podcasting is another way of listening to the radio, they are digital media files. Mostly audio but they can also be vide, which are produced in a series.
Podcasting attracts people who want to be able to choose their own content, just like using the internet instead of the TV and radio model of broadcast, where you tune in and stations that are playing.
Podcast listening experience is basically like getting radio and music shows to listen to on devices every day. You can automatically have new shows ready to listen to while you get on with what you're doing through the day.
Anyone can create their own show and broadcast it to the world, it doesn't take long and doesn't cost much, all you need is a computer, a mic and the internet.
Iplayer is basically a media player that has pre-loaded content on, BBC has it's own iplayer, it is an internet tv and radio service and software application. Iplayer's are useful for audiences to catch up with tv / radio shows they have missed. Example - http://www.bbc.co.uk/iplayer/radio
Content distribution fom independent producers to radio statios via broadband means independent production companies make a show, jingle or advet at their own home, hey edit it and save it as .wav or .mp3 file and send it via email, making sure i is secured. They send it to a radio broadcaster who pay for it.