The Blue Riband (/ˈrɪbənd/) is an unofficial accolade given to the passenger liner crossing the Atlantic Ocean in regular service with the record highest average speed. The term was borrowed from horse racing and was not widely used until after 1910. The record is based on average speed rather than passage time because ships follow different routes. Also, eastbound and westbound speed records are reckoned separately, as the more difficult westbound record voyage, against the Gulf Stream and the prevailing weather systems, typically results in lower average speeds.