Duplicate Content

I need to know what exactly google considers as duplicate content.
Clearly, having two different urls that produce pages with the exact same content is considered duplicated content. However, what if I have two article pages, one of which quotes the other - is that considered duplicate content?

Does google compare different pieces of a page's content to other sources?

 

Yes, and if it already exists in it's database, the dupe site has a lower chance of being indexed.

 

Thanks for the reply.
If that's the case, what happens to aggregators? are those sites considered duplicate content sites? Are they not indexed?

 

@NoamBarz
for avoid detected as duplicate content you can try to change the first paragraph and the last paragraph
just a few distinction will make is as a different content in search engine...

 

Hi,

Actually Google not allow to use duplicate content in the website. Google spam the website if they found duplicate content. And also google did'nt give value the PR of the site, google always give value the website content, your website should have a fresh and unique content.

 

Does google compare different pieces of a page's content to other sources?

 

yes, google will recognize that also like duplacate content

 

if it already exist in database than your content will considered as duplicate content, and it may cause banned from listing in search engine.

 

Well I think you have a clear idea about what duplicate content is and as for the one URL which quotes the other, it would still be duplicate (content-wise) but will not fall literally as duplicate-duplicate if you catch my drift. Also, Google doesn't go trigger-happy-ban-button over duplicates depending on the level or percentage of duplication.

Pages with duplicate content however tends to rank lower than the original publisher of the post or if you're not an authority domain duplicating over an authoritative domain with the same content.

 

Thanks everyone for the replies. However, the question I'm still wondering about is aggregators - why aren't they penalized?
Take Google news for example, why is it ok for Google news to use the snippets of copied content from different sources without being penalized? Is there a tag that declares a paragraph as copied?

 

Really very nice discussion about duplicate content. These discussion are very helpful and attractive.

 

For duplicate content google consider by Date who made it first.

 

Google always looking for fresh new content for its visitors.., Google not indexed site with duplicate content..
you can reword your content then use..

 

From Google:
# Syndicate carefully: If you syndicate your content on other sites, Google will always show the version we think is most appropriate for users in each given search, which may or may not be the version you'd prefer. However, it is helpful to ensure that each site on which your content is syndicated includes a link back to your original article. You can also ask those who use your syndicated material to use the noindex meta tag to prevent search engines from indexing their version of the content.