I've purchased a wp theme that I'll be using as my website. In the instructions it says the following. I have no idea what it means. Can someone explain it to me? Thanks.

Install Wordpress
1. Make sure you have an .htaccess file (I have provided one along with the theme so look for it in
the Documentation folder) in the root directory.
It needs to be writable by the server as the theme is being set up. After you finish with the
installation you can change the permisions to something more secure
(For SEO friendly URL's the .htaccess file uses the directive mod-rewrite. If your web server hasn't
loaded this module then it will ignore this directive. You will then need to contact you hosting
provider for more information.

thanks Mitch.