Suppose you were flying from New York to Los Angeles, and you wanted to stop and visit your aunt in Indianapolis on the way. Such a visit would constitute a stopover in Indianapolis. Some fares allow free stopovers, others allow stopovers for an additional fee, and many fares do not allow stopovers at all. Now, your flight might be routed through Indianapolis anyway, and you might even have to change aircraft there. You might think you could "beat the system" by booking a connecting flight for the next day. You usually cannot do so, since if you do not depart your intermediate point (Indianapolis) within 4 hours of your arrival there, it would normally be considered a stopover. Therefore, such an arrangement would not be allowed if the fare did not permit stopovers.