Technically, when you type in an web address for the first time, your computer/router etc have NO idea where that address it. So what it does is to send that address to a DNS server, which will reply something like "Oh, for this part of this address (like slashdot.org) go to this IP address." Your router/computer will cache that address for a while so it doesn't have to keep asking the DNS and use the IP address to go there, and send the web address over for further information (like for this story slashdot.org/story/09/..., the slashdot.org is likely resolved by a DNS, with the rest of the address resolved by slashdot.org server).
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Mandate every country to have its own port...