Pusher Channels is a real-time communication service that enables developers to add push notifications and live updates to their applications. This JavaScript client library allows you to connect to Pusher Channels from web browsers, web workers, and Node.js environments, providing features like subscribing to public and private channels, binding to events, and triggering client events. It's designed for developers building interactive web applications that require real-time data synchronization, chat functionality, live dashboards, or collaborative features.