You've made your split
screen, the big main window, and then the smaller navigation window. One
problem, when you click on a link in the small window, the small window
changes! That's quite a problem here's how you solve it, targetting
your links.
Here is an example
<a href="start.htm" target="Large">
Remember back in the <frame> tag, the name attribute? Well, that's what you put in the quotes in
the new target attribute.
There are also a few more values that can be put in that target attribute
_top - if you have a frames page and link to
another page, this gets rid of your frames
_blank - this opens a new browser window for
the linked to page