The following code defines the frameset (file main.htm):
First of all find out what is the name of your frame with contents. This is the frame where links should open. In the above code the frame name is "right":
<FRAME ... NAME="right">
The menu is loaded in the left frame as illustrated below (click on the image to open the example in a new window).
Menu items will target the "right" frame, so when a user clicks a menu item, the link will open in the right frame.
"Home" item must target entire browser window, so its target is set to "_TOP":
Item 1 and its Subitem 1 target the "RIGHT" frame:
Related note: S1007 Submenus do not extend beyond frame boundary