Observability is to identify the cause of issue , not only to observe if there is a issue . Observability uses metrics ,logs and traces which is main component of troubleshooting the issue and provide better solution to the customer.
Monitoring is tooling solution that allows teams to understand the state of their systems. Monitoring is based on gathering predefined sets of metrics or logs.
Observability is tooling or a technical solution that allows teams to actively debug their system .Observability is based on exploring properties and patterns not defined in advance.
Datadog is a monitoring and analytics tool for information technology (IT) and DevOps teams that can be used to determine performance metrics as well as event monitoring for infrastructure and cloud services. The software can monitor services such as servers, databases and tools .
The Datadog Agent is software that runs on your hosts. It collects events and metrics from hosts and sends them to Datadog, where you can analyze your monitoring and performance data. The Datadog Agent is open source and its source code is available on GitHub at DataDog/datadog-agent .
Agent,Metrics, tracing libraries, and Observability.