IAM:

IAM (Identity and Access Management) is a system that helps you control who can access what and what actions they are allowed to do in a computer system or cloud platform.

In simple words, IAM is used to manage users and their permissions securely.

IAM User:

An IAM User is a application that is created in AWS to access AWS services with specific permissions.

                                                                               (or)

An IAM user is an user with permanent login credentials to access AWS Services that are explicitly given to them.

In Amazon Web Services, an IAM user:

• Has a username and password (for AWS Console login)
• Can have access keys (for programmatic access using CLI or SDK)
• Is given permissions through policies
• Can be added to groups

IAM Role:

An IAM Role is a temporary identity in AWS that gives permissions to access AWS resources. These permissions are temporary and only specific permissions are given. Each role is created for a specific purpose.

• Has permissions defined by policies
• Does not have a username or password
• Is assumed temporarily by users, applications, or AWS services
• Provides temporary security credentials