Offset is the distance between the wheel’s hub mounting surface and its centerline. With a zero offset, the hub mounting surface is exactly at the centerline. Centerbore is the machined hole in the center of the wheel. The bolt pattern has to do with how many lugs there are on the wheel. You can find 4, 5, 6 or 8 lugs. The distances between the lugs is not always standard so be sure to consult a tire and wheel specialist before making your purchase.