The script on the previous page is fine if you want to open just one window from the page, but you may want to open more than one, containing different files, and with different sizes and features. This script allows you to dictate the file and other details in the link, as opposed to the main script in the <HEAD> section, so you can have as many windows with differing properties as you wish, or prudence demands.
The link below opens a window 400 by 200, with a full complement of toolbars, etc.
Open a new window 400 by 200This link will open the window sized 300 by 300, without any toolbars, etc.
Open a new window 300 by 300