hadoop包含4个模块
1.Hadoop Common:
The common utilities that support the other Hadoop modules.
支持其他模块的工具模块
2.Hadoop Distributed File System (HDFS™):
A distributed file system that provides high-throughput access to application data.
分布式文件系统，提供了对应用程序数据的高吞吐量访问。
【进程】
NameNode 名称节点 NN
DataNode 数据节点 DN
SecondryNameNode 辅助名称节点 2NN
3.Hadoop YARN:
A framework for job scheduling and cluster resource management.
yet another resource negitiate
作业调度与集群资源管理的框架
【进程】
ResourceManager 资源管理器 RM
NodeManager 节点管理器 NM
4.Hadoop MapReduce:
A YARN-based system for parallel processing of large data sets.
基于yarn系统的对大数据集进行并行处理的技术