Do SEO-friendly URLs really affect a page's ranking? [closed]

Question

I will let google answer to your question:

http://googlewebmastercentral.blogspot.com/2008/09/dynamic-urls-vs-static-urls.html

In the article:

Which can Googlebot read better, static or dynamic URLs? [...]While static URLs might have a slight advantage in terms of clickthrough rates because users can easily read the urls, the decision to use database-driven websites does not imply a significant disadvantage in terms of indexing and ranking. Providing search engines with dynamic URLs should be favored over hiding parameters to make them look static

Even if search engines didn't give your pages a better rank, you should still do it for the users. Any benefit for SEO is just icing on your site.

SEOmoz had an article with suggestions for URL best practices along with reasons why each is helpful for usability or search engines.

I don't think this question is readily answerable except by anecdotal evidence, since no two pages are "otherwise equivalent" enough to measure in the sense you're asking. Beyond a Google search engineer emerging and divulging the answer, if one exists that's limited to only this property, you're unlikely to get a definitive answer; more likely, you'll get a long stream of most-likelies.

But I do like the suggestion that descriptive URLs improve the user experience; I think that's true with respect to short URLs, definitely (e.g., "/help", or "/ask", etc.). One just has to decide how valuable that benefit is to the project, when weighed against the cost of creating such URL schemes, which can sometimes be pricey; I've had a couple of clients who've spent thousands on exactly this effort, with no measurable effect in search ranking whatever.

Keyword frequency and pagerank are really the two main factors in SEO.

It follows, then, that including keywords in your URLs is desirable.

e.g. http://my_site.com/article/keyword is better than http://mysite.com/article/42

All else being equal, both pages will achieve the same pagerank. Pagerank is determined by how many people link to you and what their page rank is. So, it does not affect your pagerank.

But it does affect how high you will end up in the search results. In the search index, not only page rank but also keyword relevance matters. If you have the keywords in your url and someone searches for them, then your page will be more relevant and be higher in the search results. Also, when people link to you then the keyword-rich URLs they use to link to you will also improve your relevance.

Don't stare yourself blind at pagerank. It doesn't matter that much. What matters is that you get found by people. Pagerank is only a small (and ever decreasing) part of that.