An AMI provides the information required to launch an instance, which is a virtual server in the cloud. You must specify a source AMI when you launch an instance. You can launch multiple instances from a single AMI when you need multiple instances with the same configuration. You can use different AMIs to launch instances when you need instances with different configurations.
What's is data transformation? Why do we keep talking about SQL? Here's a list of terms to help you learn the language of Matillion and ETL.