Observability refers to the ability of understanding the internal state of a complex system based on its external outputs. The more observable a system is, the easier it is to identify and solve performance issues without additional testing or coding. In the field of IT and cloud computing, observability refers to software tools and practices that collect, correlate, and analyze performance data from a distributed application, including the hardware and network it runs on. This data helps to monitor, troubleshoot, and debug the application and network more effectively, ensuring that customer experience expectations, service level agreementsm (SLAs), and other business requirements are met.

Observability is a new topic in the IT industry and is often misunderstood as an overhyped buzzword or a rebranding of system monitoring, application performance monitoring (APM), and network performance management (NPM). However, observability is a natural evolution of APM and NPM data collection methods. It addresses the dynamic and distributed nature of cloud-native application deployments, enabling better monitoring, APM, and NPM. The term "observability" comes from control theory, an area of engineering concerned with automating the control of a dynamic system based on feedback from the syste.