Glossary term
What is time series? Meaning for developers
One metric with one exact set of labels, plus all its values over time.
Learn it properly · Observability & SRELesson 2: Metrics and Prometheus: Counters, Gauges, Histograms and PercentilesThe metric types, labels and cardinality, why averages lie, percentiles, and a real Prometheus scrape of a Node service.