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 1Apache HCatalog
 3HCatalog is a table and storage management service for data created using Apache 
 6The vision of HCatalog is to provide table management and storage management layers
 7for Apache Hadoop. This includes:
 9 * Providing a shared schema and data type mechanism.
10 * Providing a table abstraction so that users need not be concerned with where
11   or how their data is stored.
12 * Providing interoperability across data processing tools such as Pig, Map
13   Reduce, Streaming, and Hive. 
15Data processors using Apache Hadoop have a common need for table management
16services. The goal of this table management service is to track data that exists in
17a Hadoop grid and present that data to users in a tabular format. HCatalog
18provides a single input and output format to users so that individual users need
19not be concerned with the storage formats that are chosen for particular data
20sets. Data is described by a schema and shares a datatype system.
22Users are free to choose the best tools for their use cases. The Hadoop project
23includes Map Reduce, Streaming, Pig, and Hive, and additional tools exist such
24as Cascading. Each of these tools has users who prefer it, and there are use
25cases best addressed by each of these tools. Two users on the same grid who
26share data are not constrained to use the same tool but with HCatalog are free
27to choose the best tool for their use case.  HCatalog presents data in the same
28way to all of the tools, providing interfaces to each of them.
30For the latest information about HCatalog, please visit our website at:
34and our wiki, at: