This document discusses knowledge management and different types of knowledge management systems. It defines key terms like data, information, knowledge, wisdom, tacit knowledge and explicit knowledge. It describes knowledge as a firm asset and discusses how knowledge has different forms, locations and is situational. It outlines the knowledge management value chain and types of knowledge management systems including enterprise-wide systems, knowledge work systems and intelligent techniques. Specific examples of enterprise content management systems, knowledge network systems, collaboration tools, and learning management systems are provided. Requirements and examples of knowledge work systems for knowledge workers are also summarized.