What does /# mean at the end of a web address?

[David]

No, the use of the hash or pound sign (#) at the end of a web address has nothing to do with Twitter hashtags. The symbol functions in URLs as a "fragment", "named anchor" or just a "placeholder", either opening the web page at the top or, if the hash sign is combined with a keyword (e.g. #gadget), it will open at a section further down the page with a particular heading. Here is one explanation of the use of the symbol in your context:

It's a "fragment" or "named anchor". You can use it to link to part of a document. Typically when you link to a page, the browser opens it up at the top of the page. But to link to a section half-way down, you can use the fragment to link to that heading (or whatever). If there is no <a name="whatever"/> tag within the page, then the browser will just link to the top of the page. If the fragment is empty, then it will also just link to the top of the page. For a fragment only <a href="#">Link name</a>, then that's just a link to the top of the current page. You often see that kind of link used in conjuction with javascript. Standards compliant HTML requires a href attribute, but if you're planning to handle the request with javascript then "#" serves as a reasonable place holder.
http://stackoverflow.com/questions/28001...sign-in-it

A similar question appeared on Y!A here:
http://answers.yahoo.com/question/index?...604AA6juCY