Big search engines like Google and Microsoft's Bing are constantly making changes in order to deliver the best search results to their users. So when it comes to optimizing your site for search, some tactics can improve your site's rankings while others can actually hurt them.

Online marketing expert John Rampton outlines several search engine optimization (SEO) mistakes in his article "SEO Strategies That Can Hurt Your Website Rankings." In this video he talks about one more: publishing duplicate content. This can be especially harmful especially now that Google is cracking down on sites that have what it deems to be low-quality content.

"It can be just the tagline of your business repeated 50 times on your website or an About Us section that's copied from one website to another site to 50 others," Rampton says. "You really need to write unique content."

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