To create MapReduce jobs you can either use the old org.apache.hadoop.mapred package or the newer org.apache.hadoop.mapreduce package for Mappers a
Old API (mapred)
Exists in Package org.apache.hadoop.mapred
Provide A map/reduce job configuration.
New API (mapreduce)
Exists in Package org.apache.hadoop.mapreduce
Job configuration is done by separate class, Called JobConf which is extension of Configuration
Class
Reduces values for a given key, based on the Iterable
Package Summary