(newbie) Two windows interacting
I have two windows, one, the 'main' window which contains a blog entry, and a 'child' window that contains item in an ordered list. Each item A-Z has a corresponding word a-z in the main window. Whever the user puts his mouse over, or clicks on a-z in the main window, I'd like the corresponding item in the child window to be brought to the top and highlighted.
I haven't had much luck looking around for answer because I'm not sure what I should be looking for. Even just some search terms would be helpful (though I prefer a nice solution!).