AWS Identity and Access Management (IAM) is a web service that helps you control access to AWS resources securely. You use IAM to control who is authenticated (logged in) and authorized (have permissions) to use the resources.
When you create an AWS account, you start with a single login identity that has full access to all AWS resources and services in the account. This identity is called AWS from the root user account and is accessed by signing in with the email address and password you used to create the account.
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