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While it's a good practice to try to flatten a site as much as possible, any site that deals with a large quantity of information is going to have some level of depth. Making sense out of rich information - making it easy to understand and follow - is one of the biggest and most critical undertakings that you'll encounter with your website.

In your quest for great information architecture, one tool that you have at your disposal is the URL structure of your site. Most medium-to-large websites have, at least, a few obvious sections. Some, such as news sites, may have many, as shown below.

As an example, hovering on the Sports menu item will produce a URL in the lower left corner of a Firefox browser. Down there you'll see that the link points to a /sports section.

When we click that Sports link, it will take us to the top page of the Sports section. For this sectional top page, there exists a feed of recent news stories.

Hovering on the OSU Football story link, we can see, in the lower left corner, that the path is /sports/beaver-sports/football/title-of-the-particular-story.

Hovering on the Prep Football story link, we can see, in the lower left corner, that the path is /sports/high-school/football/title-of-the-particular-story.

So, as a recap:

For collegiate footbal we have: /sports/beaver-sports/football/title-of-the-particular-story

For high school footbal we have: /sports/high-school/football/title-of-the-particular-story

Notice that we have something of a pattern occurring here?

What do you think the URL path for soccer would be?

If you guessed /sports/beaver-sports/soccer/title-of-the-particular-story, you would be correct.

It's no mystery why we were able to guess this. There was a pattern established between the first two, so it makes sense that the third item would follow the pattern as well. It's logical. An audience can easily follow this.

This is something that a site's architect can configure to happen automatically as content is created in your Drupal site.  The Pathauto and Token modules team up together to make this possible.