Windows PowerShell is a command-line scripting tool that lets administrators interact directly with Microsoft Dynamics AX to add users and user authentication, manage models, and manage configurations for communication between Microsoft Dynamics AX and Microsoft SQL Server Reporting Services. In addition, administrators can use Windows PowerShell cmdlets to create scripts. This term is pronounced "command-lets."
After you install Microsoft Dynamics AX, the applicable Windows PowerShell cmdlets are available from either the Microsoft Dynamics AX Management Shell or the Windows PowerShell console.
There is another a command-line utility called AXUtil, but this will be discontinued in a future version. So it's better we stick to PowerShell.
Access the Microsoft Dynamics AX 2012 Management Shell
1. On the Start menu, click All Programs.
2. Click Administrative Tools.
3. Click Microsoft Dynamics AX 2012 Management Console.
Most common cmdlets can be found at the following TechNet link.