What is Kibana and how does it relate to Elasticsearch?

Kibana is the browser-based visualization and management UI for the Elastic Stack. It connects directly to Elasticsearch and provides tools for exploring data, building dashboards and visualizations (bar charts, line graphs, maps, heat maps), and running ad-hoc search and analytics queries through the Discover interface. Kibana also includes Lens (drag-and-drop dashboard builder), Maps for geo data, Machine Learning job management, APM (Application Performance Monitoring), and the Dev Tools Console — an interactive interface where developers can execute Elasticsearch REST API queries directly in the browser.