Too Long; Didn't Read
Observability is about the ability to troubleshoot unknown issues that might happen in your application. If you are not familiar with it, I recommend you to watch <a href="https://www.infoq.com/presentations/observable-distributed-ststems" target="_blank">How to Build Observable Distributed Systems</a> and <a href="https://www.infoq.com/presentations/serverless-observability" target="_blank">The Present and Future of Serverless Observability</a> from QCon 2018.