📄️ Table of contents
Free discovery course on monitoring and observability in 7 educational lessons. Understand the difference between monitoring and observability, the three pillars of metrics logs traces, the four golden signals, SLI SLO SLA and the error budget, and the Prometheus Grafana OpenTelemetry ecosystem.
📄️ 1 · The problem observability solves
Without observability, you learn about outages from your customers and you diagnose by guesswork. This lesson details the five structural problems of an uninstrumented production and the real cost of downtime.
📄️ 2 · Monitoring or observability?
Monitoring watches what you planned for, observability lets you answer questions you never anticipated. Rigorous definitions, origin of the term in control theory, the notion of cardinality and history from Nagios to OpenTelemetry.
📄️ 3 · The three pillars
Understand the three pillars of observability: metrics to detect, logs to understand the details, traces to locate within a chain of services. With the costs, the pitfalls and the emerging fourth pillar, continuous profiling.
📄️ 4 · What exactly should you measure?
Latency, traffic, errors, saturation: Google's four golden signals. With Brendan Gregg's USE method and the RED method, the importance of percentiles over the average, and why monitoring CPU load is a bad idea.
📄️ 5 · SLI, SLO and error budget
Understand SLI, SLO and SLA, and above all the error budget that turns reliability into a quantified decision. How to define a good SLO, compute its budget, and why aiming for 100 percent availability is an economic mistake.
📄️ 6 · The tools and the art of alerting
Comparison of observability tools in 2026: Prometheus, Grafana, Loki, Tempo, ELK, Datadog and OpenTelemetry. Plus the rules for designing useful alerts and eliminating alert fatigue.
📄️ 7 · Real-world use cases + FAQ
How Google, Netflix and the big platforms practice observability. Famous incidents analyzed, the blameless post-mortem culture, and 14 frequent questions to get started with confidence.
📄️ 🏆 Quiz and attestation
Test your observability knowledge with a free 5-question quiz, corrected and explained: metrics, logs, traces, SLI, SLO, error budget.