It used to be simple to explain how browsing works. You type a link into the browser, the browser asks a DNS server at your ISP to translate the human-friendly hostname into the IP address of the web server, and then the browser contacts the server with an HTTP request requesting the page that you want to view.
It’s not quite that simple any more — which is rather bad news for the National Enquirer, the US tabloid which decided, three years or so ago, following a brush with the UK libel laws, that it would not publish a UK edition, or allow visits to its website from the UK. Unfortunately, the Enquirer’s blocking is no longer working as effectively as it used to.