Let's go through some important concepts related to CloudWatch:

• The CloudWatch service consists of three components, namely the CloudWatch component, the CloudWatch logs component, and the CloudWatch events component, all of which can be accessed from the console and using APIs and the CLI. Let's go over what these components do:
  • The CloudWatch component support alarms, metrics, and dashboards.
  • The logs component provides log streams and log groups so that we can log data from our applications. 
  • The events component support notifications and also auto-remediation using AWS Lambda.
• AWS provides us with some metrics out of the box and also allows us to create custom metrics for our applications.
• We can see the metrics that are available by clicking on Metrics from the left sidebar of the CloudWatch console. 
• CloudWatch integrates with other services such as SNS, Simple Queue Service (SQS), AWS Lambda, AWS Auto Scaling, and more for notifications and auto-remediation. 
• Under Alarms in the left sidebar, we have a dedicated option to set up a Billing alarm.
• Important operations that are supported by the default EC2 metrics include CPU utilization, disk read and write operations, network in and out operations, and status check failures.