IAM in AWS stands for Identity and Access Maanagement.
It is like an account management system, where you can create different user accounts and roles to control the access to the AWS resources

IAM Users

Here is an example of an IAM account that I made for the Cloud9 Access

IAM Roles

Here is an example of the different security groups and roles that I had created in AWS. These are visible in Visual Studio 2013.
I assign these to different users and groups to control the access levels

IAM Groups

Here is an example of the groups I created for use with my other AWS resouces, these can be deleted when not needed

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