A permalink is a URL that points to a specific blog or forum entry after it has passed from the front page to the archives. Because a permalink remains unchanged indefinitely, it is less susceptible to link rot. Most modern weblogging and content-syndication software systems support such links. Other types of websites use permanent links, but the term permalink is most common within the blogosphere. Permalink is a portmanteau word made from permanent link. Permalinks are often simply stated so as to be human-readable.

Now, if you are using wordpress or for that matter any other CMS, it’s imperative that the first thing you do post installation is to change the permalinks of your site. If you’d ask me why? I’d say:

1. Because it gives a good structure to your site and your site map looks pretty neat.
2. Because it’s imperative if you are looking to make your site search engine friendly

Let’s see what are the various options available in wordpress for setting permalinks:

By default if you do not change your permalinks structure of your wordpress site, it’ll look something like this:

http://localhost/?p=123: This is highly Search Engine unfriendly and doesn’t give a good look to your structure

The other options are:

Day and name

http://localhost/2008/08/28/sample-post/: Looks pretty good and I think this is the best option available to use.

Month and name

http://localhost/2008/08/sample-post/: This one’ pretty ok too but for a blog that has more than one post a day you might want to re look at this. Good for blogs which are updated occasionally in a month.

Numeric

http://localhost/archives/123: Again almost useless as it doesn’t tell the search engine bots what the URL is about.

Custom

This one’s pretty self explanatory. You can choose the way you want your permalinks to be.

Now that you know what are the various ways of creating permalink for your wordpress. You might also want to look at the page slug for other pages that you have created and change them as per your choice of permalink structure. You can find a complete guide at the official wordpress site.