Hadoop Ecosystems Listing

A non-exhausted Hadoop Ecosystems are listed in the below. The list is taken from the nice read
Hadoop the definitive guide / Tom White.

Avro
A serialization system for efficient, cross-language RPC and persistent data storage.
1. Hadoop Distributed File System (HDFS)
A distributed filesystem that runs on large clusters of commodity machines.

2. Hive
A distributed data warehouse. Hive manages data stored in HDFS and provides a query language based on SQL (and which is translated by the runtime engine to MapReduce jobs) for querying the data.

3. HBase
A distributed, column-oriented database. HBase uses HDFS for its underlying storage, and supports both batch-style computations using MapReduce and point queries (random reads).

4. MapReduce
A distributed data processing model and execution environment that runs on large clusters of commodity machines.

5. Oozie
A service for managing workflows of Hadoop jobs

6. Pig
A data flow language and execution environment for exploring very large datasets. Pig runs on HDFS and MapReduce clusters.

7. Sqoop
A tool for efficient bulk transfer of data between structured data stores (such as relational databases) and HDFS.

8. ZooKeeper
A distributed, highly available coordination service. ZooKeeper provides primitives such as distributed locks that can be used for building distributed applications.