Refer to the following information provided by Apache Hadoop for MapReduce application references:
If Hadoop API is used
Hadoop project top page
http://hadoop.apache.org/mapreduce/
Getting started
Release page
Documentation
MapReduce project page
http://hadoop.apache.org/mapreduce/
MapReduce tutorial
http://hadoop.apache.org/common/docs/r1.0.3/mapred_tutorial.html
Note: The samples and explanations in the above tutorial are based on the "org.apache.hadoop.mapred" packages, but these packages are not recommended for the current stable Hadoop version. Use the tutorial content for reference only since some of the content does not apply.