APPENDIX B: Common Properties of Module File Formats
They're all chunks of bytes. Heh heh. ;) OK, seriously now.
All mod files contain a header identifying the file and its format. It also mentions song name and number of patterns in the song. The header is usually followed by the pattern and sequencing information. Finally, the file also contains the sample data. This usually takes up most of the space in a mod. With today's file formats advancing more and more, those are just about all the common properties worth mentioning, IMHO. For further information on particular mod types, refer to the format description. This is usually found in the same archive as the tracker it is connected to. You can also check some of the audio information sites we covered in the Samples sections..