How to set a cookie in iframe? How Facebook cookies work?
<p>I'm trying to understand the principle behind the Facebook plugins.
As I understood they set a cookie when you login, and then whenever you visit a website with their plugin installed, they are abel to recognize your userId..</p>

<p>I'm trying to do it on my own on a couple of different domains I have, but I don't know where to start actually...</p>

<p>I set a cookie TEST when I visit site1.com with a random id value</p>

<p>but then when i visit site2.com what should I do? I can I read the previous cookie that contains my id?</p>
