Serverless Developer Guide
Fundamentals
With IAM, developers attach policies, JSON documents that deﬁne granular permissions, to 
resources. IAM provides pre-built AWS managed policies for common access levels. You can also 
deﬁne your own policies with the least-privilege level necessary to complete tasks.
Information about IAM policies may come at you fast. If it gets to be too much, put it in PARC:
• Principal: entity that is allowed or denied access
• Action: type of access that is allowed or denied
• Resource: AWS resources the action will act upon
• Condition: conditions for which the access is valid
At a high level, these four terms should be enough to get you started connecting serverless 
resources.
Account prerequisites
But, before you start, you need an AWS account. The following sections provide the best practice 
steps to create an account and an administrative user.
Sign up for an AWS account
If you do not have an AWS account, complete the following steps to create one.
To sign up for an AWS account
1. Open https://portal.aws.amazon.com/billing/signup.
2. Follow the online instructions.
Part of the sign-up procedure involves receiving a phone call and entering a veriﬁcation code 
on the phone keypad.
When you sign up for an AWS account, an AWS account root user is created. The root user 
has access to all AWS services and resources in the account. As a security best practice, assign 
administrative access to a user, and use only the root user to perform tasks that require root 
user access.
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