This document provides an overview of ISO 27001 and information security. It begins with defining what information is and its lifecycle. Next, it defines information security, risks, threats, and vulnerabilities. It then introduces ISO 27001 as the leading international standard for information security management systems and describes the components of an ISMS. Key aspects of ISO 27001 such as its requirements, annexes, and history are summarized. Finally, the document outlines user responsibilities for maintaining information security.