Hey Val,
They’re the same thing in almost every case – if you have a situation where you feel like they’re not the same thing, let us know about it in more detail! We might be able to recommend some alternative solution that works better for you.
But, in general, if you activate the license on http://example.com, that is one website and is one domain name. You could not then take the same license to use on a site called http://other-example.net, for example.
I hope this helps – let us know if it does!
Thanks,
George