|The principal of patching is quite easy. Just make a CD-Image file using CDRWIN, then use the patch to modify this CD-Image, so it adds a trainer or it removes a protection. Then this CD-Image is written back to a CD-R and the result is a "Patched" game.
The older patches contains an executable (*.EXE) which modifies the CD-Image (so no extra tools are needed). Most of the current patches use the PPF Patch Engine (*.PPF) to apply the patch. This is a separate tool which must be extracted to the same path as the CD-Image and *.PFF file. Sometimes a APPLYPPF.EXE PC PPF Patcher is already included in the Patch Archive then nothing more is needed to apply the patch. For more detailed information on PPF download the latest PPF-O-Matic from PDX.
Patches with the P4U extension need the PAL4U Patcher to apply the patch to a CDRWIN CD-Image.