Wordpress - Wordpress and event-driven programming - what is it about?

First of all lets clarify what paradigm word means in the programming. It means that we come to an agreement that we will handle certain cases/issues/situations in a certain way.

For instance, we come to agreements that foot-passenger should cross a road on a green light in our country. This is our green light paradigm. In another country could be an agreement to cross a road on a raised hand. That is their raised hand paradigm. They are not related to each other, they just exists and foot passenger could use either paradigm or create his own cross a road whenever I want paradigm.

The same situation is in the programming. Paradigm is just a set of rules or agreements to develop an application in a certain way or use a certain approach. Nothing more.

Ok, get back to WordPress and event driven paradigm. This paradigm is only one part of whole WordPress system. This paradigm sets a bunch of rules/agreements how to extend the core by 3rd party extensions, where hooks for actions and filters are linchpin approach. Pay attention that this paradigm covers only expansibility cases/issues/situations and this is not only paradigm used by WordPress, but is one of the core ones.

That's all. Of course you can use your own write a plugin/theme how I want paradigm and be happy with it :)

I think that with event driven paradigm, who write article intends Observer Pattern.

And that in WordPress is handled via the Plugins Api. I don't think there's much more to say.

@nicolai: Wordpress follows Publisher Subscriber variant of The Observer pattern (Event Driven Architecture).