The biggest advantages of using frames is to save loading time. Things like navigational bars that allow your users to get around your site can be loaded once into a frame and never again, thus saving time. The biggest drawback is the overhead in maintaining the frames. You will need to know exactly how each HTML page on your web site will be loaded. As you add and remove pages from your web site, you will begin to notice the everlasting headache of remembering just which frame files show up where and where the linked documents from a particular page should show up.
Frames also make bookmarking web pages virtually impossible.
Since a framed web site uses a master file to lay out the initial web pages to form a single web page, a bookmark can only track the outter frameset. This means, the initial pages that were loaded. Some web browsers have put in a lot of work to story individual frame states, but nothing solves the problem of trying to email a friend a URL from a framed web site. If you've even clicked a single time, you've typically moved off the front page and down into the deeper content into the web site. You'll notice that the URL on your web browser will not have changed even though you've loaded new content.