AWS IAM allows an administrator to provide multiple users and groups with granular access. Various user groups and users may require varying levels of access to the various resources that have been developed. We may assign roles to users and create roles with defined access levels using IAM.

It further gives us Federated Access, which allows us to grant applications and users access to resources without having to create IAM Roles

https://aws.amazon.com/iam/#:~:text=With%20AWS%20Identity%20and%20Access,to%20refine%20permissions%20across%20AWS.