Why Frames are Deadly in SEO
Chances are, if you've done much work as a webmaster, you know a little bit about frames. As the name indicates, a frame page is an HTML code that frames other pages. It looks quite nifty on a website, and, once you have the coding down pat, it isn't that difficult to set up. So what's the problem?
The problem, at least from a search engine's point of view, is that there's nothing there to see, and certainly nothing to index. That nifty little code you used to create the webpage is the only thing the search engine will see. From a spider's point of view, there's nothing there. There's just some code; no real content.
There are ways to work around the problem, such as, for example, using the <noframes> tag. But by the time you've created content for the <noframes> tag, you might as well have created the entire site without the frames to begin with. In the long run, it would have been easier. Instead of creating site + <noframes> content, you could have simply created a website without frames, and saved yourself the trouble.
And the question arises: is it really worth it? Granted, frames look nifty and are fun to play around with. But ninety-nine times out of a hundred, there is some other way of working your webpage so that the frames aren't really necessary.
If frames are necessary, then create optimized content for your <noframes> tag that search engines will be able to read and index. Pay close attention to your TITLE and META tags, since these and the <noframes> tag are the only things search engines will be able to use. It's much more work than creating a straight HTML site would be, and your site will probably never rank as high as it would if it were straight HTML.
If you have the option, avoid frames. They simply aren't worth the extra effort required for good SEO.