POML (Prompt Orchestration Markup Language) is a structured markup language designed to enhance prompt engineering for Large Language Models (LLMs) by addressing issues like format sensitivity and data integration. It features an HTML-like syntax, comprehensive data handling, and a templating engine, facilitating the creation of modular, maintainable prompts. The toolkit also includes IDE support and SDKs for various programming languages, streamlining the development process for LLM applications.