If you’re familiar with the dialog editor in Visual Studio then you’ll probably recognize the script dialog editor, as it was very heavily influenced by the Visual Studio original.
The four main parts of the dialog editor are:
Commands: Commands for editing the dialog including positioning and alignment tools.
Workspace: The main area where the dialog is designed.
Control Palette: Controls you can add to the dialog.
Properties: Edit the properties of the dialog and controls.
See Creating Script Dialogs for information on how to get to the dialog editor.