AWS Identity and Access Management (IAM) is a web service for securely controlling access to AWS services. With IAM, you can centrally manage users, security credentials such as access keys, and permissions that control which AWS resources users and applications can access.
Identity and Access Management---IAM---User Guide
|• IAM User Guide
|• IAM API Reference
|• IAM CLI Reference
|• AWS IAM Access Analyzer
|• Security Token Service---STS API Reference
|• Security Token Service---STS in the AWS CLI Reference