Wave, Midi and RealAudio are the three audio file types used most on webpages.
I haven't explored MP3; the files are extremely large.
Waves (.wav) can be played through accessory programs provided by Win95.
They sound crackly, at times, but can be adequate.
The files tend to be very large, therefore they are used primarily for short clips.
Example 1
Example 2
Wave files are used at the following site:
One is embedded to play automatically;
the second is played when you click the 'friend Mandy' index entry.
http://www.erols.com/brittanyetal/index.htm
Midi (.mid) can also be played through programs in Win95.
The files play with less noise, but most times sound a bit too synthesized,
at least on my system with SoundBlaster16. Percussion sounds are
produced accurately, but the organ, especially, sounds toy-like.
I'm sure more expensive sound cards do a better job in rendering
the sounds, but I doubt the majority of web surfers have this costly upgrade.
Example 1
Example 2
I use midi here: Click on the music button; five songs are randomly played,
so you'll have to close the small window and click again to hear all the selections.
Java-enabled browser required, too.