According to Google's Matt Cutts (In a Webmaster Central Blog posting dated Dec 1, 0
, they've changed the algorithm to prevent duplicate content penalties in pages using IFRAMES.
Using IFRAMES, even when they contain content from other sites, will no longer harm your rankings and, on the flip side, external content won't help your rankings either.
Here's some more info from SEO Roundtable:
Google Fixes Spam Algorithm Classifier For IFrames
That being the case, there might several issues to consider before implementing IFRAMES.
- Are you hoping the iframe content will help with your SEO efforts or are you simply using it to improve user experience?
- If you place links to the local page content being displayed in the IFRAME, what happens when the page shows up in the SERPS and a user clicks the link? Will the page load itself into the parent page or will the page be orphaned and out of context with no way to find the originating website?
- Would using CSS to display the content serve the same purpose?
- Does it matter to you if the IFRAME content doesn't pass any SEO benefits to your site?
This page might help you better evaluate your options:
SEO & iFrames: A Glimpse at What Search Engines See : StraightUpSearch
While they certainly have their uses, before suggesting IFRAMES, I'd recommend using CSS and/or include files.
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