Dashes or underscores ?

What should i use in the url, dashes or underscores?
The url is rewritten and it`s like website.com/this-is-the-url or website.com/this_is_the_url

 

use dash like website.com/this-is-the-url

 

What about with like directories? For example...When you add a two or more word catagory to phpld. It puts the sub as example_example automatically. So in your browser you see www.widgets.com/this_subcatagory Should I change these to www.widgets.com/this-subcatagory...

Also, what is the difference? What makes one better than the other?

 

i was looking at digg, it uses underscores
I reall don`t know what to do. People advise me to use dashes for seo, but underscores look better.

I would definitely use dashes if i knew for sure it`s better for seo

 

Dash makes the url appear as multiple words to the bots, underscores make it appear as one word.

Here's a great post from Vanessa Fox (via Matt Cutts), towards the end of the post you'll see the discussion of hyphens.

 

I've try both in the past. For my sites dashes work better

this-is-the-best-way

 

Hmmm...well it makes sense if it is true that this-site is considered two words and this_site is considered one word. That was a great article thank you! Now my question though is how do you know that -'s equal two words and _'s equal one word?

 

Well I think the fact that the article is from a couple of Google employees makes it seem pretty reliable.

 

Hmm sorry I didn't realize it was from google employees...well I guess I got some work to do to change it in my new directories...

 

From my personal experience, I can chip in and say:

Bad experience = underscores
Good experience = dashes

 

Dashes.

You'd be surprised how many people don't know what an underscore is - much less how to make one on their keyboard.

 

thank you, i have chosen dashes

underscore = _ and you make it by pressing shift + dash

 

Oh Ya I totally know how to make an underscore.

But I use to work at a nation wide ISP help desk and use to have to explain the concept of an underscore and how to make one all the time.

 

that depends on your req if u whant to show as 1 word then use _ or else -.i used even _ and had good results.we have to use acc to req

 

Its really difficult for me to gauge dashes or underscores, on www I read dashes are much better, however I have seen numerous examples (sites) which are scoring on top and using underscores, need a definitive reason here what should be use and WHY ?