If you are new to WordPress, you have the ability to fix the permalink structure of your URLs as per your choice. Once your links are linked back by thousands of websites and indexed by search engines, it is difficult to change your permalink structure as it will lead to all broken 404 links.
WordPress provides a very user-friendly way to customize your permalinks easily. Just in case you did not know, permalinks mean the permanent URL of your post. WordPress codex has an excellent article on Using Permalinks.
Change Permalinks Settings
You can change your entire blog permalink structure with one click only. It is a powerful tool, use it carefully. After you log in to WordPress, go to Options, then Permalinks. There you can choose
Date and name based
And the powerful way is to customize it as per your liking too. What I am using is
Why I Chose Date Based Permalinks
I removed the day part of the code in my custom permalink, more in line with what Blogger does. You can also include hours, minutes and seconds into your post URL. Amazing!
I was tempted to remove the date part altogether and just add post name, such that I could have neat URLs like http://www.sitename.com/postname but they warn that
If you use postname as the only element in your permalinks to create a structure such as myblog.com/post-title, the rewrite rules may make it impossible to access pages such as your stylesheet (which has a similar format) or the wp-admin folder. It’s best to include some numeric data (e.g. the post ID or date) in the permalink to prevent this from happening.
On the codex page, I pointed above, you can try many more advanced permalink tricks with .htaccess, mode_rewrite, etc., but be very careful with what you do. This is a powerful tool and can change the entire URL structure with one click only. So it is a good idea to fix your permalink structure when you start with WordPress.