Level 1 (L1) construct

Direct representations of CloudFormation resources.

Must provide all the required CloudFormation attributes.

They are named CfnXyz.

▪ Level 2 (L2) construct

Represents a particular cloud resource. S3 bucket. You

don’t have to configure every configuration attribute.

higher-level, intent-based API. s3.Bucket class represents

an Amazon S3, such as bucket.addLifeCycleRule()

▪ Level 3 (L3) construct = Pattern Construct

Represents a bunch of cloud resources that work

together to accomplish a particular task. You can create

an ApplicationLoadBalancedFarageteService. Higherlevel constructs, which we call patterns. 

https://docs.aws.amazon.com/solutions/latest/constructs/welcome.html