An ocean current is a continuous, directed movement of seawater generated by forces acting upon this mean flow, such as breaking waves, wind, the Coriolis effect, cabbeling, temperature and salinity differences, while tides are caused by the gravitational pull of the Sun and Moon.
RDDs - Radar Detector Detectors, All Acronyms, viewed April 15, 2017, <https://www.allacronyms.com/RDDS/Radar_Detector_Detectors>.
A Global distribution system (GDS) is a database capable of storing and updating enormous information on the supply of a wide range of tourism products worldwide. GDS enable the travel agents to access, in real-time, availability, features and prices of flight tickets, hotel rooms, rental cars, cruises, ferry reservations, trains and other services.