Custom Templates
When creating pages and articles you can also create custom templates to go along with specific content.
When creating a new page take note of the slug you create and use this to appaned to the template file name:
http://mydomain.com/about-me
The custom template would map to:
themes/default/page-about-me.php
This is also true for articles:
http://mydomain.com/blog/hello-world
The custom article template would map to:
themes/default/article-hello-world.php