What really is duplicated content?

I'm confused with this

[MisterAoD]

Hi there,

I have some concern about duplicated content. If I developed a website with my own layout, my own style of html alignment. I made it from scratch, but on that site I have some free articles from various source posted. Will this be considered as a duplicated content?

Or could you please specify what makes SE consider it as a duplicated content that lead to the banned of website. (Well, at least could you give me old discusstion thread links)

Any advice is appreciated, thank you :)

[Patrick Taylor]

I'm not the expert on this, but I know there is a lot of duplicated (and triplicated etc) content on the web. All other things being equal, in many or most cases it doesn't lead to a ban. More a case of Google not wanting the same content duplicated in its SERPS. I've read here several times that the page with the highest PageRank (for a particular version of duplicated content) will perform better, and others are simply dropped way down, but not banned as such.

[gellydonut]

Can anyone offer insight into the handling and possible penalties for duplicate content within a site?

I have pages of product listings that allow the user to order the listings by different criteria and manage the number of products that are displayed. Each combination of sorting criteria generates a unique url for ease of bookmarking but each of these urls then contains essentially the same content. Is it possible the site could be penalized for this?

Thank you so much for any advice you can offer!

[Reid]

The reason duplicate content is considered SPAM is because SE's don't want to return a page of search results all leading to the same article. This specific article has just the right amount of keywords to outrank all others for a given search and we end up with 2 or 3 competing results for the same "content".
The web is built upon hyperlinks. Why do you need to waste valuable resources to copy/store/serve content that you can link to?
It is always best to use you own material and if something exists on the web that you want to show others then link to it.
A paragraph can be penalized as duplicate, wonder how a whole article will fare.
The duplicate content filter will 'assume' the original version of the article and filter others out of the results because they want to provide a page of "different results" to the user.

[Stefan]

but on that site I have some free articles from various source posted. Will this be considered as a duplicated content?

The pages won't automatically be filtered out as dupe content if there are appreciable differences on the rest of the page (along with the different domain, etc), but you'll be competing against a lot of other sites that are also using the same articles, so don't expect it to be seen as original content and ranked accordingly. (Imho, and I know there are others with different opinions.)

Each combination of sorting criteria generates a unique url for ease of bookmarking but each of these urls then contains essentially the same content.

That doesn't sound good. Don't take this as gospel, but you might wind up with only one of them being listed eventually, probably the one that has the best PR. You can't feed identical pages to the bots with different URL's - it's bound to cause problems.

[tigger]

Lets say you have a book affiliate site

You build pages around book themes and use the reviews found from the main site.

so each page will have say 6 books with a snippet of information from each book review

would that be classed as duplicate content as you will be using these snippets from the main site on a page that will have some of your own content as well?

I hope I've explained myself well LOL