New Relic

One telemetry database (NRDB), NRQL, APM and distributed tracing, and applied intelligence

New Relic's defining choice is that everything lands in one store, NRDB, and everything is queried with one language, NRQL. Metrics, events, logs and traces are not separate products with separate query syntaxes, so a single NRQL statement can join across them. Interview questions usually start there: why a unified telemetry database simplifies correlation, and what you give up in exchange. Expect to be asked how the agent auto-instruments a framework and when you would drop to a custom instrumentation API instead, how distributed tracing reconstructs a request across services, and how applied intelligence groups related alerts into a single issue rather than paging you eight times for one outage. Data retention and ingest-based pricing come up often, because they shape what teams choose to send in the first place.