Google’s duplicate content penalties can feel like strict punishment for web-sites that get attacked. Most marketers are aware of these actions and run their sites accordingly. However, what is not well-known among SEO circles is what actually constitutes “duplicate content” and how domain owners can be certain that their web sites are in compliance. A web site owners worst nightmare is finding out the hard way that their search ranking has been lowered and that they’ve been removed from Google’s index altogether.

You can make sure you’re on the right side of Google’s rules by understanding the idea of “duplicate content” and make sure that you’re not in violation of Google’s policies.

First, you should know that Google’s grounds for punishing those with duplicate content are actually quite reasonable. The fact is, Google wants to avoid search results pages overwhelmed by websites with the same or similar content, and with good reason; duplicate information makes it difficult for searches to find what they’re looking for.

Google created a new patented “fingerprinting” technology to prevent the appearance of duplicate content on different websites. By recording an initial “fingerprint” of a site, Google can periodically compare the “fingerprints” of various sites in a database and lower the value of sites with content copies.

There are several examples of web sites and web site content that can be considered duplicate and, surprisingly, you’ll find that most are unrelated to spam. Here are just a few:

PLR Content: The most common case penalized by Google’s duplicate content policy is using PLR articles or other free articles in exchange for a link.

Mirrored Sites: It’s quite common to “mirror” a site in order to balance the amount traffic on the server and enable sites to divide hits received between two identical sites. This practice is effective in balancing server load and eliminating downtime in loading, but the site copies are considered duplicate content.

Let’s say you own the .com, .net, and .org versions of your URL or versions with common misspellings of your URL. Rather than only redirecting traffic to a single URL, it may be wise to include some of your content, a newsletter, or free downloads on these pages.

Domain Sub-Niches: If you have a sub-niched site, you should use subsets of keyworded content. For example, if you write articles on personal finance for single moms, you may want to leverage your articles by creating sites targeted to special topics, such as “single-moms-savings-tips.com” and “single-moms-debt-help-tips.com.”

Dynamically Generated Content and/or Templates: The use of RSS feeds from blogs and news/article syndicates amount to a greater amount of duplicate content on web sites. Dynamically generated templates in Content Management Systems (CMS) or shopping carts may also register as duplicate content. NOTE: This example applies only to feeds that display as static HTML. If you’re using a javascript feed to attract visitors, it can’t help your SEO, but it also can’t trigger a duplicate content flag, since Google’s bots can’t read it anyway.

Doorway Pages, Cloaked Pages, “Bombs,” and Automated Directory Pages: Regardless of how promising this new technology may sound, Google is quickly catching up and examining every new script and tool. Thus, these pages should not be used for any reason other than market testing, seeking out quick-leads, or as means of driving temporary traffic through “throw-away URLS.” It’s critical that value-added content and customization be incorporated on web sites with such tools.

Site Navigation Elements and Other “Content”: It’s important to understand the broad definition of content by which Google evaluates web sites. The arrangement of items on your page, your internal link wording and structure, outgoing links and anchor text, lead capture forms, graphics, product descriptions, prices, merchant-provided sales copy and articles, and other on-page variables all fall under the category of “content.” Each element can be singled out for violation of duplicate content rules.

Theft: Theft also applies to more than simply written material on your site. If your page designs, links, or even entire website show up elsewhere, Google may lower you in the rankings or remove you from its index totally.

Now that you have a good grasp on the idea of what consists of duplicate content it’s time to make sure you are not in violation of Google’s policies. The Google administration always seems to catch on to things that are being done to try to “fool” them. It’s always a better idea to stay with white-hat procedures when you’re working with something as important as your reputation.