I have a web application that provides information related to the weather. I am trying to make this information as discoverable as possible. My question is, is it a good idea to post the same content, multiple times, under different URL paths? For instance, what if I had the same content posted at:
http://www.mydomain.com/weather/[year]/[month]/[day]/index.html and http://www.mydomain.com/weather/[year]-[month]-[day]/index.html
Will search engines block your site if you do this?
You won't likely be blocked, but having multiple URLs with the same content might dilute the SEO value of the page since the two pages will essentially be competing against each other for the same keyword hits.
No, they won't block you, but this could possibly bring down your ranking. The solution that Google reccommends is to add a meta tag to each of the pages that has the same content specifying a "canonical" URL that the search engine should reference:
<link rel="canonical" href="http://www.example.com/path-to-content" />
See the article here on the Google Webmaster blog for more information.
In addition to the above, note that the prior answers are focused on how to explain to search spiders that the content is identical, and should be treated as a single piece of content.
So...
If you have not already created the duplicate content, do not create it in the first place - it dilutes the effectiveness of the content.
I suggest you start with making your content as useful as possible - this inherently will strengthen its relevance.
Then, while you are busy doing that, start reading the Google blogs to build up your knowledge of standard SEO practices (e.g. not posting duplicate content in an attempt to boost page popularity).
Then, once yo have useful content, look into ways to optimize that content for best/most effective exposure to search engines.
