Sound Formats

There are many computer formats for sound, and theoretically any of them could be used in a web page. The three most popular formats (those most likely to work on your readers' machines) are WAVE, AU, and MIDI.

WAVE (Waveform Audio File Format, with the file extension .wav) was invented for Windows by Microsoft. AU (Audio File Format, file extension .au) was invented by NeXT and Sun. Both are now widely accepted on many platforms, and are common on web pages. WAVE and AU are like sound recordings... they reproduce recorded sounds (or computer generated sounds). They also tend to be big files for just a little sound. WAVE and AU files are good for a short sound effect such as a short greeting or perhaps a cow moo. (Notice that the size of that moo file is 21.5 KK for only about one second of sound.) There is also a recorded sound format called AIFF (Audio Interchange File Format), invented by Apple and SGI, which is widely supported, but is far less popular than AU and WAVE.

MIDI (Musical Instrument Digital Interface) is an entirely different concept. The MIDI file format is a series of commands such as "play middle C for .25 seconds". These sort of commands are very small, so one of the great advantages of MIDI files for your web page is that a lot of music can be packed in a small MIDI file. This rendition of "Hazy Shade of Winter" is only 16K but plays for over two minutes. The downside of MIDI is that it takes a real master to work any expressiveness into this electronic command-based format. MIDI music tends to have an uninteresting "easy listening" quality to it, making your web page seem like a dentist office.