In the last couple of weeks, we've heard the great news that the default version of Joomla 1.5 will produce more Search Engine Friendly URLs than the current package.

The forum post has turned from happiness to suggestions about what the new URLs should look like.

One of the key questions was whether underscores should remain in the URL or if dashes would be better.

Should URLs be www.joomla.com/1.5-is-now-out or should it be www.joomla.com/1.5_is_now_out ?

The answer is simple: 

• Dashes are better for searching. Matt Cutts, the Google engineer, gives a technical explanation of this on his blog.
• Dashes are better for readability. As Ken, the developer of Open-SEF points out, underscores are much harder to read, especially if they are in a link that is underlined.
• Dashes are actually used in English. See if you can name 10 English words with a - in them. Now see if you can name 10 English words with an _.
  

If you have a well-established site using underscores, is it worth moving over? Probably not, because of all the time it would take to reindex your site, but for all new sites, dashes are definitely the best bet.

Proof of this idea can be found with three simple searches:

• search engine friendly     26,300,000 Google results
• search-engine-friendly     1,530,000 Google results
• search_engine_friendly     476 Google results