Permalinks are the ‘secret sauce’ to successful referral linking, and the more people linking to you,  the higher your rank on Google.   A permalink is the permanent identifier to a specific weblog post or article.  Because blogs tend to be frequently updated, articles you find on a weblog’s homepage one day may not be there the next.   A permalink is the permanent identifier to a specific weblog post or article.

Bloggers love permalinks — they provide an easy way to capture specific references to posts or articles about which bloggers are writing.   A permalink is what another weblogger will use to link to your article (or section), or how you might send a link to your story in an e-mail message. The URL to each post should be permanent, and never change — hence permalink.

By default, WordPress and popular blog software publish your pages like this:
http://www.unilyzer.com/p=119

Permalinks transform your URLs to look like this:
http://www.unilyzer.com/internet-marketing/wordpress/

The second example with the permalink is superior for two reasons:

• Permanent – When you update your article or make changes to it, the link will not change. In the first example, each time you update your post the number will change. The result is that all your incoming links will see the error message page can not be found.
• Search Engine Optimized SEO – Look how the second example uses keyword phrases in the link structure, this is important when it comes to getting indexed in Google.

I recommend the following permalink structure for WordPress. Using the category name and post name is the best way to search engine optimize your links.

In the Settings → Permalinks panel (Options → Permalinks before WordPress 2.5), you can choose one of the “common structures” or enter your own in the “Custom structure” field using the structure tags. In the “Custom structure” field type: /%category%/%postname%/

Set-up screen for WordPress Permalinks

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