As far as there is many ppl who don't realize what JDM is I post this entry. Copied from Wiki =)
The term Japanese domestic market (JDM) refers to the local market in Japan for Japanese-made motor vehicles and components. Within the car and motorcycle hobbyist import scene, this term, and the related term Japanese domestic model, most commonly refer to Japanese-brand automobiles and parts designed and constructed to conform to Japanese vehicle and equipment regulations and to suit Japanese market preferences.
Basically means each market has slightly different parts for the same car in their market. These slightly different parts can be swapped (with little or no effort) to any other of the same model car from a different market.
For example, power folding side mirrors from a JDM Civic to a USDM one.
JDM vehicles often differ in features and equipment from vehicles sold elsewhere. For example, Honda has produced many different versions of the B18C 1, B16A and K20A engines for various markets worldwide. This is done due to varying emission regulations in different countries. Internet-based navigation systems have been installed in most vehicles sold in Japan, and as of exporting, those navigation units are beginning to turn up in export markets. Honda's system is called Internavi, Nissan's is called CarWings, and Toyota's system is called G-Book. All three systems use cellular connections from the driver's cellphone for activation, which might be compatible with satellite navigation systems deployed internationally.
