gosh, people, can't you read?
imagine a website
www.abcd.com
that's the name of the company, and the company hosts the website with a hosting company.
now that company sets up their office network with the domain abcd.com (it should be abcd.local, but there are no real restrictions)
everything abcd.com is now, for office workstations, being resolved by the internal DNS server that works with active directory. but the company website is not there, it is in a completely different place on a webhosting farm.
the result is: website is accessible to everyone in the world, except for the company employees, because the internal DNS server resolves it internally, and doesn't forward a query for it to the root servers.
In order to make the website accessible to company employees all you need to do is go into the internal DNS server configuration and add an A record for
www.abcd.com with the IP of the website, so it can be internally resolved.
what you guys are talking about is bypassing protective filters, I am talking about a common misconfiguration that lots of small companies have to get around.