1) Your link is very clear as to what Modal Window is all about.
2) Other type of Window/Form (Child, Topmost, SplitChild) still pending to find the accurate description.From Wikipedia:
In user interface design, a modal window is a graphical control element subordinate to an application's main window which creates a mode where the main window can't be used. The modal window is a child window that requires users to interact with it before they can return to operating the parent application, thus preventing the workflow on the application main window. Modal windows are often called heavy windows or modal dialogs because the window is often used to display a dialog box.
3) Your personal opinion is highly appreciated..... Thanks
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Hi Javier Tovar,
Althoug I don't speak/read Spanish, I can feel that your answer is logical and helpful...... Thanks.