not really years (though that has to do with it) but the changes in styles. like mine is the 5th generation of the civic. so the 5 design change. usually called a 5th gen, or an eg. eg, ek, ej, ep... all have to do with chassis codes. they represent different trim levels (cx/dx/ex/si and so on). a list of those can be found at http://www.jdmfan.com/index.php?info...=chassis_codes