Offset: Offset is the amount of "offset"  a wheel has in relation to where the mounting location is compared to rim width. Example: A 5" wide wheel with a 3+2 "Offset" means there is 3" from the mounting surface to the hub from the outside edge of the wheel and 2" in the rear. A 5" wide wheel that has the mounting surface directly in the center would have a offset of 2.5"+2.5" but you won't see that. A wheel that has a "offset" of 4+1 would cause the vehicle to be wider than one with a 3+2 or 2+3 "Offset". Sometimes this is called backspacing.

Utility Tires and Wheels: Utility tires and wheels are tires and wheels you would find on a work or hunting style ATV or on a UTV. These usually are in the 12" to 14" rim height range.

Rim Width and Tire Width: Tire and wheel width do not normally match. Example: a 12" wide tire will fit on a 7" wide wheel. The wheel width is always smaller than the tire width.