Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Zooko''s triangle is a diagram named after Zooko Wilcox-O''Hearn which sets out the possible tradeoffs for a system for giving names to participants in a network protocol. At the vertices of the triangle are three properties that are generally considered desirable for such names: Secure: The quality that there is one, unique and specific entity to which the name maps. For instance, domain names are unique because there is just one party able to prove that they are the owner of each domain name. Decentralized: The lack of a centralised authority for determining the meaning of a name. Instead, measures such as a Web of trust are used.