As we interact online we are creating new kinds of knowledge and community. How are these communities formed? How do we know whether to trust them as sources of information? In other words, Should we believe Wikipedia? This book explores what community is, what knowledge is, how the internet facilitates new kinds of community, and how knowledge is shaped through online collaboration and conversation. And the most important question of all: What can we as internet users and designers do to help the internet to bring out the best in us all?