Erlang is emerging as a leading language for concurrent programming in mission-critical enterprise environments where applications must deliver exceptional reliability, availability, and scalability. It's already used by organizations ranging from Facebook to Amazon, and many others are adopting or considering it. As a functional language, however, Erlang is radically different from conventional object-oriented languages like C++ and Java. This book quickly brings experienced object-oriented programmers up to speed with both Erlang and the principles of functional programming. Jerry Jackson thoroughly explains Erlang's key concepts, principles, and features, bridging the conceptual gaps that often frustrate object developers. Next, he shows how to use Erlang to build massively-scalable real-world systems with up to "nine nines" availability: that is, up to 99.9999999% uptime. Coverage includes: " What Erlang is, and why Erlang offers so much potential " What it means to be "concurrency-oriented," and how to design concurrency-oriented applications " How to use functional features, pattern matching, and Erlang's standard libraries " How to manage concurrency and mutable state, and work with the Mnesia database " How to write distributed software with Erlang " How to interact with Java, C, and other languages " How to use Erlang's bundled web server and debugger