Data exchange with different pages

[Alexancho]

I am creating a page that is some kind of a mediator between different pages:

1. From one page a client sends a form.
2. A page-mediator does some checks and actions, makes decisions and sends data to a third side page.
3. The third side page do something and sends data to the mediator.
4. Mediator again does something and sends notification to the client.

In a common flow when we use form submitting or header("Location: ...") the client will see all the redirection, pages reloading etc. But the aim is to make the client dialing with mediator page only. The better thing is to send to client some message on the stage 2 and continue with the third side separately.
Is there the way to do that?

[Mordax]

Perhaps you should look into AJAX, which will allow your server to do its thing and pass the finished data back without the client leaving the page he/she was on at all

AJAX is a very broad topic and I don't have time to go into detail, but I thought I'd at least point you in the right direction