Types of EC2-Instances
There are different types of EC2-Instances types which are defined for certain use cases and unique requirements for different workloads and different applications depending on your use cases like depending on the computing, memory, or storage you required. for more read Amazon EC2 – Instance Types
What is Amazon Machine Image (AMI)?Pricing Of AMI
An Amazon Machine Image is a special type of virtual appliance that is used to instantiate (create) a virtual machine within EC2. It serves as the basic unit of deployment for services delivered using EC2. Whenever you want to launch an instance, you need to specify AMI. To launch instances, you can also use different AMIs. If you want to launch multiple instances from a single AMI, then you need multiple instances of the same configuration.