This book provides a good introduction to WebRTC and helps get a web developer started with building an application with WebRTC. This is how the book is organized:
An overview chapter covers the concepts and provides demo url’s so readers can test out a demo WebRTC application.
A technical chapter talks about the various API’s (WebSockets, MediaStream and RTCPeerConnection) and provides some best practices.
The next few chapters talk about individual features such as video, audio, text (chat) and file sharing. These chapters also walk through the code to implement each of these features.
Finally, the last couple of chapters provide example applications. This is more overview in nature.
Overall, a good book and a good introduction to WebRTC.