PalmDOC

PalmDOC, or AportisDoc, is an e-book and text document format that was popular on PalmOS devices.

It is usually found in the form of a PalmOS Database (PDB) file. Even if the file extension is .prc, it is probably in PDB format, not PRC format.

See also MOBI, an extension of PalmDoc.

Identification
In PDB format, ASCII characters appear at offset 60.

Sample files

 * http://cd.textfiles.com/pdasoftware/PILOT ...
 * E.g. CALORIES.PDB, CHI-FUN.PRC, JOKES.PDB

Links

 * MobileRead Wiki: PalmDOC