[tialaramex]

Something is a _secret_ only if at least two people know it. This makes a tremendous difference because now either of them might betray the confidence, a _private_ fact can't be given away by anybody else, it is yours to keep private or not.

Society blurs this line a lot by telling people things are "Private" when in fact they're only a secret, and then there is an opportunity to betray them. This happens for payment cards for example, bank representatives have been known to tell even a court of law that bank employees can't find out your PIN, so if a PIN was used it proves the customer was negligent or actively participated in the transaction. In fact, of course, the PIN is a secret, so the bank and thus its employees are aware of the customer's PIN and an insider could in fact perform transactions using PIN verification despite no negligence by the customer.