Non-stop flights are flights where the aircraft makes no stops between its initial and final destinations. They are flights without a connection or lay-over in cities other than the desired travel destination.
Non-stop flights tend to be more expensive than flights with connections because they are more desirable to most travellers. Non-stop flights usually offer a shorter overall travel time with more amenities. Direct flights are different than non-stop. Direct flights are flights where the aircraft lands, but many passengers stay on board awaiting the next take-off. The longest non-stop flight in service is a 17 hour flight from Dallas, Texas to Sydney, Australia.