An information hazard or infohazard is "a risk that arises from the dissemination of (true) information that may cause harm or enable some agent to cause harm". It was formalized by philosopher Nick Bostrom in 2011. It challenges the principle of freedom of information, as it states that some types of information are too dangerous, as people could either be harmed by it or use it to harm others. One example would be the instructions for creating a thermonuclear weapon. Following these instructions could cause massive amounts of harm to others, so limiting who has access to this information is important in preventing harm to others.