Twisted is an event-oriented network framework in Python. This book is written by leading Twisted experts who will demonstrate the uniqueness of this framework and introduce you to the projects to which they have personally contributed. Practical examples illustrate how the Twisted architecture facilitates testing, solves common reliability issues, debugs, and facilitates the identification of causal relationships. Asynchronous programming techniques are described and the importance of deferred calling of functions and coroutines is emphasized.