Whenever we provision any kind of resource, we will automatically get an overview of the metrics of that resource available from the CloudWatch Overview section, as can be seen in the following screenshot:

By clicking the Overview section, we have the ability to select each service individually and take a look at a nice graphical representation of the metrics for each service:

When the Overview section does not provide the metrics that we want to quickly glance at, we have the ability to create dashboards where we can customize the way the metrics are displayed. We can select metrics from one service or metrics from different services in one dashboard and thus create a simple way to view the metrics that are relevant to the health of our application.