Monitor is used for getting the information about the node flow status in various forms (graphical metrics, Audit and scheduled task (job) which is running in the background).
It consists mainly three tabs-
Metric tab, you will get the information about nodes like error, http, http status code, http response time, flows, nodes (types), CPU and memory etc.
Task consist of background job details if any scheduled.
Audit consist of the user information who deployed the application at which time.