Is there any books or websites that somebody could suggest to start a reading for knowing about data warehousing? Also let me know the application or usage of data warehousing.

Since you have mentioned you want to start your learning for this the best book would be
Building the Data Warehouse by Bill Inmon
and the Data Warehouse Toolkit by Ralph Kimball.

visit Kimball Group: Data Warehouse Training, Consulting, and Kimball University, it has truckload of information.
DataWarehousing.com - documenting data replication and data transformation
sites on the Net for information & discussion forums.

Thank you. The reference has lot of information to make study on data warehousing. Kindly post if you happen to get any information useful to make with data warehousing so that we can enrich our knowledge

Well, Ryan, The basic intention to build the data warehouse is to have a single version of truth of the historical enterprise data. The data warehouse building strategy is generally driven by the Reporting Requirements.

Because, DWH is built on Dimensional Data Modeling, & has OLAP structure, it enables users to slice & dice the information parameterizing on different dimensions.
For E.g. : Sales volume can be seen by different dimensions like Time(year, Qtr, Month tec.) , Region(Country, state, city etc.), Product(Lines, Category, products)

DWH helps you in query & analysis of historical data for Strategic Decision Making. DWH is used for Enterprise Reporting, Ad-Hoc Reporting, Analytics, Forcasting etc.

hope this small explaination helps you a bit.
Cheers,
Pat.

There is a book on datawarehouse by Ralph Kimball.
You can give a search as 'Data Warehouse Concepts' in google.
You can even search the 'IT Toolbox.'
Data Warehouse is a place ,rather a database where historical data are stored.On the basis of these data analyst or top level managers can take decisions for more profit making of the organisation.It helps in decision making and strategy planning.

thanks for the information.this information is really useful for me.

please kindly give references about SAS datawarehousing..