The document discusses several technologies for building real-time web applications, including PSGI/Plack, AnyEvent, AnyMQ, AMQP, comet techniques, WebSockets, and Web::Hippie. Specifically, it covers:
- PSGI and Plack for building web applications and middleware in Perl.
- AnyEvent for asynchronous programming and handling connections.
- AnyMQ for message queueing with support for AMQP via plugins.
- Comet techniques like long-polling for server-push capabilities before WebSockets.
- The WebSocket protocol standard and APIs for bidirectional communication.
- Web::Hippie for building real-time web applications in Perl using WebSockets.