What is Danger?
{{redirect|Risk|the board game|Risk (game)}} [[File:Achtung.svg|thumb|[[Traffic sign]]s which are triangular with a red border are warning drivers about something dangerous. This one simply has an [[exclamation mark]], so it might refer to any kind of danger.]] '''Danger''' (also '''risk''' or '''peril''') is the possibility of something bad happening. A situation in which there is a risk of something bad happening, is called ''dangerous'', ''risky'' or ''perilous''. [[File:Train Surfing in Soweto.jpg|thumb|left|Train surfing in [[Soweto]] ([[South Africa]])]] People often take risks, or do things that might hurt them. An example of this is crossing the road without looking carefully. There is a risk that you might get hit by a car. Anything that involves a risk of [[injury]] or to health can be described as dangerous. [[Smoking]] is dangerous to health. Being around some animals is dangerous because they might attack humans. == Measuring danger == There are a few different ways that danger can be ''quantified'' - put into numbers. === Probability === [[probability]] measures how dangerous something is. It uses a math equation to find the risk that a certain event might happen. In [[epidemiology]], risk is defined as the number of events that ''did'' happen, divided by the number of events that ''could have'' happened. For example, if the risk of [[Infant mortality|babies dying after birth]] in a [[population]] is reported as 1/1000, it means that out of every 1000 babies born, 1 is likely to die. === Risk and prevalence === [[Prevalence]] is the number of people in a population that have a certain [[disease]]. Risk is the number of ''new'' cases of disease, divided by the number of people who ''could'' get the disease. For example, during an outbreak of the flu, risk would be the number of people who get the flu, divided by the number of people who were [[Exposure (toxicology)|exposed]] to the flu [[virus]]. ==== Risk assessment ==== A risk assessment is a list of things that could go wrong. In many