Book excerpt: Covering the basic concepts and principles of Information Technology (IT), this book gives energy managers the knowledge they need to supervise the IT work of a consultant or a vendor. The book provides the necessary information for the energy manager to successfully purchase, install, and operate complex, Web-based energy information and control systems. Filled with comprehensive information, this book addresses the most significant concepts and principles that the typical energy or facility manager might need with emphasis on computer networking, use of facility operation databases, and sharing data using the Web and the TCP/IP communications protocol.