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>.
Resilient Distributed Datasets. Resilient Distributed Datasets (RDD) is a fundamental data structure of Spark. It is an immutable distributed collection of objects. Each dataset in RDD is divided into logical partitions, which may be computed on different nodes of the cluster.