I think having hierarchies in url will be user friendly but will it be good for SEO? which of the following urls will be good for seo? URL SET 1 ----------- sitename.com/module/category-name/ - which will display all the titles in that category and sitename.com/module/category-name/title-of-the-post/ - which will display a specific article in a specific category in both cases the category-name is real dynamic category name like sports, health, news etc... (or) URL SET 2 ----------- sitename.com/module/category/ - will list all categories sitename.com/module/title/title-of-the-post/ - no category name is mentioned - the /title/ subfolder section is static for all article links or instead of the second url if we are going to follow the url set 2 i think this will be very crisp sitename.com/module/title-of-the-post/ so the question is all about how much it makes sense for seo if we have hierarchy in url? if so then it will be user friendly else we have also seen wikipedia which have sitename.com/title-of-the-post so please suggest?
It is not very good to have an extended hierarchy for your site with its folders and sub-folders. Try to limit them to at the maximum 4-5 steps down. As for as your URL sets are concerned, set 1 is better... sitename.com/module/category-name/title-of-the-post/ - It clearly tells the user and the search engine about the category, module and the title which is optimal for rankings.
I use three tiers on my site, home page, category, articles. Spiders do not always get to any more levels, it may take months and months for the 4 and 5 to get indexed.