According to Google's Webmaster website, duplicate content is having large quantities of content that appears to be the same across various websites on the Internet. The majority of the content completely matches other content with minimal differences or appears to be similar.
Google's primary goal is to provide users (customers) the best search experience possible on the Internet so they will seldom display websites with duplicate pages of content and therefore, the algorithm chooses the website that is most likely to be the originator of the content.
Websites that have pages with duplicate content run the risk of being delisted or not showing up on the query results for keywords.
What about quoting or using content from other sources, will Google see that as duplicate content and penalize your website? Hear what Matt Cutts from Google has to say:
Click HERE to read more about duplicate content at Google's Webmaster Tools…
Are their any guidelines for developing content on my website?
Yes there are. Content plays a MAJOR factor with Google and the search engines. If you want to develop content so that it shows up on Google's search engines, you must play by their rules and adhere to their standards.