What are the three pillars of observability in microservices?

The three pillars of observability — Metrics, Logs, and Traces — together provide the visibility needed to understand system behavior and diagnose problems in a distributed microservices environment. Metrics are aggregated numerical measurements over time (request rate, error rate, latency percentiles, CPU usage) collected by Prometheus and visualized in Grafana — ideal for alerting and trend analysis. Logs are structured (JSON), timestamped records of discrete events emitted by services, shipped to Elasticsearch or Loki — ideal for detailed debugging of specific incidents. Distributed traces (Jaeger, Zipkin, AWS X-Ray) capture the end-to-end journey of a request across services — ideal for understanding latency and service dependencies. Each pillar answers different questions; together they give operators the context to debug issues that would be invisible in isolation.