AIFF sound files are the standard file format defined by Apple and several third-party developers for sampled (digitized) sound.
However, Windows only works with AIFF in a few applications. Windows uses .WAV files as its own file format for digitized sound. Unless the application you are using in Windows works with AIFF files, a simple transfer of the sound file won't provide a usable Windows sound file.
The AIFF sound file has header information that can be followed by a variety of "chunks." One of these chunks represents a linear sampling of audio waveforms stored as bytes. A general overview of AIFF files is in Chapter 22, The Sound Manager, of Inside Macintosh VI. A more complete description of the AIFF file format is available from Apple's developer web site at:
http://www.apple.com/developer/
Nothing in the Windows/MS-DOS environment can directly understand the header information. Therefore, you need to do a file conversion. There are several Macintosh applications and shareware utilities that allow you to convert AIFF files into WAV files.