RealAudio and Real Video technology utilizes an interactive system between the Real Video Server and the Real Player to enable real-time audio and video delivery over the Internet. When the user clicks on a link on a Web page, the clip buffers and then begins to play, all within a few seconds. This gives the deceiving impression that the file is linked directly to the Web page. In reality, information is passing between the Web server supporting the Web page, the Real Video Server supporting the file, and the Real Player.

How does streaming audio/video work?
The file itself is not linked through the web page, contrary to general belief. Information actually passes between the web server, the Real Server, and the Real Player. RealAudio and Video can only be retrieved by the Real Player. If you have a link to the actual file on your server, the file will be downloaded completely before it can be played by the Real Player. There needs to be a go between the web server and the Real Server. This go between is a metafile. This metafile provides the URL of the file to be played to the Real Player.

What is a Metafile and how does it work?
Metafiles are text files which contain the URL location of a RealAudio or Real Video file. Remember that RealAudio and Real Video files cannot be referenced directly by the Web page because this would cause them to be downloaded in their entirety before playback. In order for the files to be played in real-time, they must be played through a Real Player, and served by a Real Video Server. Therefore there must be a link between the Web server and the Real Video Server. The link is contained in the metafile.

I've got RealAudio installed on my site, but it's not streaming. It's downloading the file and then playing it. I didn't want it to do this!

You need to have a metafile call the file itself.

Typically you'll create a RealAudio file subdirectory under domain-www, and put all your audiofiles there.

Then your .ram file, a.k.a., metafile, will contain an address with this format:

http://fulldomainname/subdirectory/filename.rm

The "subdirectory" is a subdirectory of your domain-www directory.

So for example:
http://musicforyou.com/ra/music.rm

Notice:
The above address goes in the .ram/metafile, not in your HTML code. Your HTML code calls the .ram/metafile. Then the .ram/metafile is used to call up the .rm/realmedia file. So for example, your HTML code would look something like this:

<a href="http://musicforyou.com/ra/music.ram">Click here to listen to music.</a>

Where can I get more information about creating Real Audio/Video files?

You can find this information at Real Networks Site.