What are the three pillars of observability?

Answer

The three pillars of observability are metrics, logs, and traces. Metrics are numeric time-series data, such as request rate or error count, that are cheap to store and ideal for dashboards and alerts. Logs are timestamped records of discrete events, useful for detailed, contextual debugging. Traces follow a single request as it flows across services, revealing where time is spent and where failures occur in a distributed system. Used together, they let you detect, diagnose, and understand problems.