Although there are numerous differences between AWS Lambda and Amazon ECS, the following are two of the most significant ones:
Amazon ECS is a highly scalable, high performance container management solution using which you can simply execute apps on a controlled cluster of Amazon EC2 instances whereas AWS Lambda is a serverless compute service that runs your code in response to events and automatically manages the compute resources for you.
You have a central repository called Amazon ECR where you can store your Docker Images from ECS containers. On the other hand, with lambda you must construct an execution role with the required permissions in order to grant your Lambda function access to other services, such as Cloudwatch Logs.
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