This document discusses the importance of data warehousing for multinational corporations (MNCs). It notes that MNCs often struggle to find, understand, and use the data they need because data is scattered across networks in many different versions and formats. A data warehouse integrates data from various sources into a single consistent store that is easy for end users to access and understand. It allows historical data analysis and "what if" scenario planning to help answer business questions and make better decisions. The document outlines key components and architectures of data warehouses and how they can provide summarized data to different departments through data marts.