It looks simple enough now, and sounds pretty good, although we hear clearly that technology is still pushing the envelope when the sound skips.  However, when Progressive Networks introduced RealAudio in 1995, musicians and their audiences weren't sure whether to laugh or cry.  Until then, the only way to pass music through the Web was to provide an audio file for download and later playback.  At 9600 bps, the wait for the download of a 30-second extract was never worth the occasional pleasant surprise when you actually liked the music.  Waiting for a full track with a decent sound was unthinkable.  RealAudio clearly defined the compromise: if you want to hear it now,  you can't hear it quite so nicely.  Originally designed for speech, the codec (enCOde/DECode) sounded almost unbearable on rock+roll, even assisted by early cuts from the Rolling Stones, and unspeakable on classical music.  But it had arrived, and would improve dramatically.

Today, with far faster modems and a quality which can be adjusted to suit the fastest transmission rate of your own system, it's possible at least to check out whether you like the music or not, and do it almost as efficiently as you might scan tracks on a CD.  The player now has video rolled in, it's now called RealMedia, and the company is RealNetworks.  For streaming audio, RealNetworks used to be the market leader, but has lost ground to Flash and mp3 streaming.

As we mentioned in Audio On The Web, the trick for streaming audio is to dispatch a steady stream of data packets and get them all to line up in time and in order at the client computer.  Specialized servers are necessary, and encoding is complicated.  From the user end, all that is needed is a player, and as fast an internet connection as possible.