Not quite sure if this would be helpful to anyone but overall correlation does not necessarily equal causation. For example, people who tan for longer amounts of time on the beach are more likely to get attacked by a shark. While it may be the case that this is true, it may also be the case that people who tan for longer amounts of time on the beach may use scented tanning oils in order to intensify their tans. Upon making contact with the water, the scent of the tanning oil attracts sharks, increasing the likelihood of a shark attack when compared to individuals who only tan for short durations of time. The tanning oil in this case is the "confounder" or lurking variable, which explains the overall increase in likelihood for those who tan for longer to also be attacked by a shark. So, although there is an existing positive correlation between people who tan for a prolonged duration of time and shark attacks, it need not be equated with one necessarily causing the other as there is an existing confounder.