## TL;DR

Grafana (2014, Torkel Odegaard) is the leading open-source observability platform for dashboards, alerting, and data visualization. It queries 30+ data sources (Prometheus, Elasticsearch, InfluxDB, PostgreSQL). Grafana 10 (2023) introduced Scenes (dashboard as code) and Correlations.

## Core Explanation

Dashboards: panels (graph, stat, table, heatmap, geo), variables (dynamic filtering), annotations (event markers). Alerting: unified UI with Prometheus Alertmanager integration. Explore: ad-hoc query interface. Loki: Grafana's log aggregation system (Prometheus for logs). Tempo: distributed tracing. Grafana Cloud: managed observability stack (free tier: 10K metrics, 50GB logs).

## Further Reading

- [Grafana Documentation](https://grafana.com/docs/)