In general, data warehouses and data marts support business intelligence (BI) applications.

Business intelligence is a broad category of applications, technologies, and processes for gathering, storing, accessing, and analyzing data to help business users make better decisions.

A data warehouse is a repository of historical data that are organized by subject to support decision makers in the organization. Because data warehouses are so expensive, they are used primarily by large companies.

A data mart is a low-cost, scaled-down version of a data warehouse that is designed for the end-user needs in a strategic business unit (SBU) or an individual department.

Data marts can be implemented more quickly than data warehouses, often in less than 90 days.

Further, they support local rather than central control by conferring power on the user group. Typically, groups that need a single or a few BI applications require only a data mart, rather than a data warehouse.