RAGHack is a multi-day hackathon running across 25+ live streams where participants learn to build RAG applications combining large language models with search engine knowledge. The event covers building AI apps on Azure AI in multiple languages (Python, Java, JS, C#) using retrievers like AI Search, PostgreSQL, and Cosmos DB, and frameworks including LangChain and Semantic Kernel. Participants submit hacks for prizes while learning about agents and vision models.