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AWS Identity and Access Management (IAM) is a web service that helps us securely control access to AWS resources. We can control authentication (who can signed in) and authorization (who has permissions to use resources) using IAM. An IAM user doesn’t have to represent an actual person; we can create IAM users in order to generate an access key for an application that needs AWS access. It is possible to grant different permissions to different people for different resources. IAM is free to use. We will be charged only when we access other AWS services using our users credentials.