Introduction to observability concepts

Observability both as a word and as a discipline is not unique to technology. The term is derived from control theory, which is traditionally more rooted in physical engineering disciplines such as robotics and nuclear engineering. It is, in essence, the ability to surmise the health of a system by observing its inputs and outputs. In nuclear engineering, you put in uranium and water, and you receive heat and steam. In software engineering, you put in an end user and an API call, and you receive a Jira ticket about how your API isn’t working. Err… well, hopefully not if your observability is doing its job.

Observability in systems engineering and software is primarily informed by and achieved with a handful of important telemetry signal types. You may have heard them referred to as “the three pillars of observability,” but that terminology has since fallen out of fashion as it elevates the act of gathering telemetry...