A Data Warehouse is a database-centric system of decision support technologies used to consolidate business data from many disparate sources for use in reporting and marketing. analysis (Data Warehouse). Data warehouses and data warehouse systems are primarily used to provide executives, senior managers and business analysts with accurate and consolidated information from various internal and external sources to facilitate the process of making complex business decisions ( data warehouse process). The term data warehouse was first coined by Bill Inmon, who has been commonly recognized as the "father of data warehousing" and is the leading proponent of the standardized approach or sometimes called the top-down approach to design of data warehouses (Reed, M.)(Data Warehouse). In this data warehouse model, all organizational data is collected from source systems at the lowest level of detail, called "atomic" data, and stored in the data warehouse. This data is then grouped into subsets of the original transactional systems based on model-specific business processes called data marts (for example, a marketing data mart could contain all the data from the entire organization related to the marketing department). This design allows for high consistency across business processes because all organizational information is loaded into the data warehouse simultaneously and all data is linked by common dimensions (the data that gives context to transactions, such as customers ( dimension) to purchases (transactions) or employee (dimension) to sales (transactions)). But as the scope of this design encompasses all organizational data, necessitating the need to model, develop and deploy the solution as a whole, this results in a significant investment in terms of paper..... .esearch /articles/a-definition-of-data-warehousing-16730/ >“Extract, transform, load” Wikipedia Wikimedia Foundation, 2011. Web. Nov 30, 2011 Shaik, Sadip “ETL Architecture and Business Models” sadiqblog.com Exploring Analytics Feb 28 2008. Internet. November 30, 2011Bowman, David “Data Warehouse Basics” information-management-architect.com DavidBowman's Information Management Checklist 2009. Web. November 30, 2011< http://www.information-management-architect.com/data-warehouse-basics.html>“What is a Data Mart” learn.geekinterview.com GeekInterview January 13, 2008. Web. November 30, 2011< http://www.learn.geekinterview.com/data-warehouse/data-marts/what-is-data-mart.html>“Data Warehousing Basics” amar-padhi.com amar le June 5, 2009. Diagram. December 2, 2011< http://www.amar-padhi.com/oradb_dw_basics.html>