From an observability point of view, the system under observation (SUO) is made up of a collection of sources. These sources emit telemetry signals, such as logs, metrics, and traces, which we discussed in chapter 2 and which form the basis for actionable insights for humans and machines alike.
In the context of cloud-native systems, things tend to move fast—new open source projects are launched, providers add features to their products, and cloud providers introduce new services. It is for this reason (that is, the iteration speed found in cloud-native systems) that we won’t go into great detail about specific offerings, their APIs, or their features. What is important and what I’d like to focus on is to enable you to understand which sources are at your disposal and which ones you may wish to select for a certain task.