In this article, the author discusses Identity and Access Management (IAM) policies in Amazon Web Services (AWS), which are crucial for access management on AWS. IAM policies determine what an identity or resource is allowed to do on AWS based on a set of permissions. They are primarily stored in JSON format and can be accessed through the AWS IAM console. The author provides an overview of various types of policies supported by AWS, including identity-based policies, resource-based policies, permissions boundaries, Organizations Service Control Policies (SCPs), Access Control Lists (ACLs), and session policies. The article then delves into creating and managing IAM policies using Terraform, an open-source infrastructure as code software tool that automates the provisioning of cloud resources. The author provides a step-by-step guide on how to create a user with Terraform, create inline policies, represent policies in various ways such as HEREDOC syntax and jsonencode function, create standalone IAM policies using Terraform, attach standalone policies to a user, use aws_iam_policy_document data resource, and associate an AWS managed policy with a user. The author concludes by stating that all these learnings can be extended to any other type of AWS-supported policy and provides examples on how to create resource-based policies using Terraform. The key takeaway from this article is the importance of mastering IAM policies for effective access control management on AWS, and how to use Terraform to manage them efficiently.