WordPress with different widgets in different categories

Hello All,

I would like to know, is it possible in WP, to post different (ads, widgets, images) on the page, under different ID’s, and how I would do that.

An example is Joomla. Different modules, displayed under different categories or sections.

How can I do that in WP. Display different widgets or different areas with the content, on different pages, or even better be able to have a different layout, depending on the section.

The reason for all of that, I am using OPENX for ads on my site. And I want to be able to have an ability to have different ads under different sections.

Thanks in advance for your help,

-Fast4u