Wordpress question

Hello,
For my first informational and news website I did everything myself including the content management system with php and mysql. With the second one, I want to try wordpress, but I am very unfamiliar with it except knowing that it is a popular CMS...

1) Is wordpress database made of mysql? Just asking if later I am not happy with it I can migrate the content to a normal site and display as I want with php...

2) As far as flexibility, how does it compare accordig to making your own site yourself? For example if I want to add applications, calendars, newsletters, mobile stuff or anything you can think of...does it have category pages for example?

3) In other words, and most importantly, does it allow you to build like a non wordpress site as well - in case you want greater flexibility?

Wordpress is mainly a blogging software and isn’t as flexible if you want to use it as real CMS since its concept is more post based than page based. You can have pages but flexibility and control over templates and stuff isn’t as good as with CMSs like CMS Made Simple, Drupal, or Joomla.

Of course, there are thousands of plug-ins for almost any need that you just plug in and activate. Wordpress is made for the people, not for the developers so the interface is intuitive and stuff is usually easy to use. You can also write your own plug-ins if you’re down with PHP (hah! that reminds me of a song somehow… “you down with PHP? Yeah, you know me!” :D).

Yes, Wordpress consists of PHP and MySQL. You should read the documentation on their website, it answers many questions. Also there is a demo (http://php.opensourcecms.com/scripts/details.php?scriptid=88) so you can try it out before you use it.