How does streaming of web radio basically work?

My sister is a totally internet radio freak. She listens to internet radio all the time. So I thought why not write a little funny styled app for her upcoming birthday ;-)

I'd like to understand the concept behind streaming online web radio. As I never listened to online radio myself I need some advice from you guys.

Questions in my mind: Is a stream just a file which I "open"? Does it have an URL just like any other web ressource?

My goal is to write an application that takes an stream URL, and then just plays that stream. However, I was reading somewhere else that I need to have my own server hardware with complic开发者_开发技巧ated software to convert audio and stuff like that. I mean... really? Aren't there programs for windows already that play any web radio with a given URL out of the box with no third party server in between?

Note: I don't want to stream myself, but I want to listen to a stream. Sorry for my bad english. I don't want to send out a stream. Just receive one.

There are quite a lot stream software providers. Most are free. The most known are: Shoutcast Icecast

But if you are looking for a web application that does this someone made there while ago: PHP radio

Also Wikipedia has a nice article about how webradio's work: Wikipedia

Microsoft used to offer Windows Media Encoder (built with wma codec 9) that could stream and do static conversions. I haven't seen any recent update to this though....