This document discusses key concepts related to data warehousing including: - The definition of a data warehouse as a subject-oriented, integrated, time-variant collection of data used for analysis and decision making. - Common features of data warehouses such as being separate from operational databases, containing consolidated historical data, and being non-volatile. - Types of data warehouse applications including information processing, analytical processing, and data mining. - Common schemas used in data warehousing including star schemas, snowflake schemas, and fact constellation schemas.