You can now create runbooks of a new type in Azure Automation – PowerShell. PowerShell runbooks allow you to automate processes by using PowerShell commands rather than PowerShell workflows. This makes using Azure Automation easier because it allows you to take full advantage of the service by using your existing knowledge of PowerShell. It also allows you to use existing PowerShell scripts in Azure Automation.
PowerShell runbooks also enable faster testing and execution. Unlike PowerShell workflows (which have a compile step with a duration that scales as the size of the runbook and number of inline runbooks grows), PowerShell runbooks have no compilation step. This means that PowerShell runbooks of any size and complexity should start within seconds in Azure Automation.
For more information, please see Announcing Native PowerShell Script Support in Azure Automation