This tutorial series explores the Vonage Video API (formerly TokBox OpenTok) and its capabilities for building robust and customizable video chat applications. The series starts with creating a basic audio-video chat application using Glitch, a Node.js server, and vanilla JavaScript, and then moves on to implementing more advanced features such as session creation, token generation, and streaming. The tutorial covers the basics of how the Vonage Video API works, including initializing a session, connecting to it, publishing and subscribing to streams, and handling errors. It also provides a comprehensive overview of the API's capabilities and limitations, as well as resources for further learning and troubleshooting.