The MPW Shell command language was based on the Unix csh language, but was extended to support the main features of the Macintosh GUI. It had simple commands to create menus, dialogs (prompts), and new shell windows. The cursor could be controlled, and MPW scripts or tools could easily be attached to a menu item. Command key shortcuts could be specified. Window size and location could be controlled. These features were popular in commercial production environments, where complicated build and packaging processes were all controlled by elaborate scripts.