The concept of observability traces back to the 1960s, with Rudolf E. Kalman’s canonical work around decomposing complex systems for human understanding. It was a heady time for new compute systems in aerospace and navigation. The advances in these systems exceeded humans’ ability to reason about them, and Kalman’s work is largely credited for laying the foundation for observability theory.
Observability as we know it today—the $9 billion category that is a staple of modern IT operations—is more commonly associated with Google’s site reliability engineering approaches to hyperscale services like Google Search, Google Ads, and YouTube.
