A site's URL structure should be as simple as possible. Consider
organizing your content so that URLs are constructed logically
and in a manner that is most intelligible to humans (when
possible, readable words rather than long ID numbers). For
example, if you're searching for information about aviation, a
URL like http://en.wikipedia.org/wiki/Aviation will help you
decide whether to click that link. A URL like http://www.example
.com/index.php?id_sezione=360&sid=3a5ebc944f41daa6f849f730f1, is
much less appealing to users. Consider using punctuation in your
URLs. The URL http://www.example.com/green-dress.html is much
more useful to us than http://www.example.com/greendress.html.
We recommend that you use hyphens (-) instead of underscores (_)
in your URLs. Overly complex URLs, especially those containing
multiple parameters, can cause a problems for crawlers by
creating unnecessarily high numbers of URLs that point to
identical or similar content on your site. As a result,
Googlebot may consume much more band