The idea of selecting websites which might be opened is controversial. While it’s generally thought to prevent children from watching explicit content, Web filtering was never as white as it was supposed to be. Avoiding pornography, racist content and violence was the need that led to inventing the idea of spam filter . Further appliances got significantly out of trace. As more and more filters have been allowing full customization options, people decided to use them in slightly different way. It would be enough to mention workplaces, for example. Managers used to block all the sites that aren’t a part of company’s inner network, so the workers got significantly restrained. It had to increase their efficiency, in fact, had increased only managers’ control. In fact, there is a lot of better-known cases of Web filter over-zealous usage. The greatest example of Internet censorship happened in China, when all the websites containing words ‘Tibet’ or ‘Dalai Lama’ have got blocked. Moreover, ‘the Great Firewall of China’ is thought to be duplicated in different regions of the World, especially in Cuba and Zimbabwe. Against all odds, filtering itself has caused a significant growth of Internet security, so it should be considered as a quite successful invention.