The series of tubes famously dubbed the ‘internets’ by president G.W. Bush* constitute a world wide web of interconnectedness. But, as this map demonstrates, there are some black holes in that web. They represent the 15 countries that limit or prohibit their citizens’ access to internet as a way of censoring the free flow of information.

Perhaps most notorious among those countries is China, with its Great Firewall (and its insistence on self-censorship by non-Chinese companies operating within the Middle Kingdom). Other countries also maintain firewalls, notably Saudi Arabia, while less-developed nations might just not allow their citizens to own computers.