Using license included instances allows you access to fully compliant Microsoft software licenses bundled with Amazon EC2 or Amazon RDS instances and pay for them as you go with no upfront costs or long-term investments. You can choose from Amazon Machine Images (AMIs) with just Microsoft Windows Server, or with Windows Server and Microsoft SQL Server pre-installed. Amazon RDS for SQL Server offers databases without the time consuming administrative tasks. Whether using EC2 or RDS, buying from AWS with Microsoft licensing included has many benefits.