Forum Moderators: Robert Charlton & goodroi
There's a simple way to check whether Google will crawl things with a certain filetype extension. If you do a query such as [filetype:exe] and you don't see any urls that end directly in ".exe" then that means either 1) there are no such files on the web, which we know isn't true for .exe, or 2) Google chooses not to crawl such pages at this time — usually because pages with that file extension have been unusually useless in the past. So for example, if you query for [filetype:tgz] or [filetype:tar], you'll see urls such as "papers.ssrn.com/pape.tar?abstract_id" that contain ".tar" but no files that end directly in .tar. That means that you probably shouldn't make your html pages end in .tar.
The SEOmoz folks stumbled across this when they had a url that ended with "/web2.0" . It looks like previously they had a url looked like "/web2.0/" (note the trailing slash), which we were happy to crawl/index/rank. But when their linkage shifted enough that "/web2.0" became their preferred url, Google wouldn't crawl urls ending in ".0", so the page became uncrawled.
Google is willing to revisit old decisions and test them again, which is what we're doing with the ".0" filetype extension.
A URL ending in a trailing slash is for a folder or for the index page in a folder.
The URL for a page should not end in a trailing slash, and it may or may not have an optional extension.
I looked through the top 30 results on Google for
allinurl:webmasterworld.com
I dont think a coincidence can explain it away. I changed the URL's over 2 months ago and they all never ranked. After I made the change and added the trailing forward slash to the end of the URL as soon as these URL's were crawled and cached in google, they start ranking again.
There are likely other factors at play here, but this is hardly a coincidence.