Are there any benefits to having dashes in file names?

[RyanWhitney15]

Through searching, I can find lots of discussion regarding "dash vs underscore", but am having trouble with an even simpler question:

Is there any SEO difference between using

http://www.broadway.com/shows/milliondollarquartet.php

vs.

http://www.broadway.com/shows/million-dollar-quartet.php

[SEOnut]

A lot of coders like giving filenames underscores rather than dashes, because when you select (doubleclick) a filename_like_this all the text is selected, whereas a filename-like-this may only have part of it highlighted - so to me, an underscore is more akin to 'treat this like a word' and a dash is 'treat this like a space' - and either is better than %20!

For SEO though, the dash=space is worth it where:

• the URL string is long (thisisnotaseasytoread in the address bar, this-is-much-easier-to-comprehend) - I think that helps users, which in turn signals to Google that you're being helpful

• if the concatenation of the words would be confusing to a stemming programme - see here for examples http://independentsources.com/2006/07/12/worst-company-urls/

• if someone wanted/had to manually type a url, a dash is quicker/easier as you don't need the shift key (which you do for an underscore)

• if someone shares (pastes) a raw, long URL, with dashes in you have a chance it will wrap in a blog or wherever -

reallylonglinkswithnospacesendupstickingoutofthesidesofablogandlookuglyandannoyingandlessprofessional

that looks dreadful, whereas you might get away with high-on-the-hill-stood-a-lonely-goatherd

• I find that it also helps with link-naming consistency, it's easier for you to spot your own typos or linking errors (so fewer 404s to hunt down)

Sorry, must dash

[TroyCarlson]

From what I've come to understand, dashes are seen as spaces by most search engines, so it helps to delineate your phrase.  milliondollarquartet would be seen as one word, while million-dollar-quartet would be seen as 3 and would be more readable by both users and search engines, and it would help you get some SEO juice for the phrase, while milliondollarquartet would probably not be searched upon.

That having been said, I'm still fairly new to SEO, so hopefully you'll get more answers.  But that's been my understanding thus far.  

[AdoptionHelp]

A smart robot can parse that out using algorithms called stemmers... But what about less sophisticated robots? Will ask.com or lesser known SE's get your keywords right without the dashes? What about a combination of words that can be separated in different ways to give different meaning?

And what about human readers? Which is easier for you to read?

Dashes and underscores are the URL equivalent of spaces. They help human readers and robot crawlers parse out what your URL is supposed to be.