MapReduceisthedistributionsystemthattheHadoopMapReduceengineusestodistributeworkaroundaclusterbyworkingparallelonsmallerdatasets.Itisusefulinawiderangeofapplications,includingdistributedpattern-basedsearching,distributedsorting,weblink-graphreversal,term-vectorperhost,webaccesslogstats