The type of intersection, and whether it has posted signs and/or signals, determines which right of way laws apply to drivers and pedestrians. While the general rule is to yield to other vehicles and pedestrians at all times when necessary to ensure safety, there are more specific right of way laws applicable to different types of intersections. For example, at a four-way stop marked by stop signs, the driver of a vehicle should yield to a vehicle on his or her right, if the two vehicles reach the intersection at approximately the same time. If a vehicle arrives at a four-way stop first, however, then that vehicle should typically proceed first through the intersection. When a vehicle reaches a two-way stop, however, in that cross-traffic on one road does not have to stop, the stopped vehicle must yield the right of way until the cross-traffic has cleared the intersection, and it is safe to proceed.