Eliza is a lightweight, open-source conversational framework that simulates a psychotherapist via pattern matching and scripted templates. Developers can define custom scripts, patterns, and memory variables to tailor responses and conversation flows. It runs in any modern browser or webview environment, supports multiple sessions, and logs interactions for analysis. Its extensible architecture allows integration into web pages, mobile apps, or desktop wrappers, making it a versatile tool for education, research, prototype development, and interactive installations.