Does Google considers duplicate content if an item on my blog appears on the first page, then in a specific category?
Don't post articles multiple times? If you are referring to blog entries where you see the blog post on the front page and then on the actual post page - that's ok though...
Is this information Your own? Or did you find it else where? If it is be sure to be careful if You are pulling Your information from other resources. There is a certain amount which needs to be altered for the information to be classified as Relevant vs. Duplicated. I could be wrong but I know for example for such things like images 30-40% must be altered for it be seen as NON-Duplicated.
If you post duplicate content,Google consider it as spamming and can decreases your website value or pagerank. So, do not post same content multiple times.
No, this will not be considered as duplicate content, because content is under one post not in two posts.
Google DOES NOT consider this "duplicate content". If that was the case, every blog on the Internet would be consider duplicate. Every blog has a "loop" on the home page which includes text or snippets from posts within the blog. This is not anything to worry about...
Is call a blurb and it contains a read more link as well the title also links to the full post. Is not consider duplicate because you are not actually publishing the whole content only a blurb.
Just would like to add one more line, as if you use duplicate content for your website, more the chances are of getting penalized by a search engines.
It is not considered duplicate content if you didn't take it from another site. If you want to do a research first before writing anything, just get the idea from the article you are getting a reference from and write your own. Your credibility lies on how much quality work you are putting and the uniqueness of the content.
I do not know the truth about duplicate content. Many Internet marketers say concern about duplicate content, but my blog (yes, duplicate content from another site) is still safe until now.