Confidentiality

Confidentiality-

In information security, confidentiality "is the property, that information is not made available or disclosed to unauthorized individuals, entities, or processes" (Excerpt ISO27000). Confidentiality is a concept similar to, but not the same as, privacy. Confidentiality is a necessary component of privacy and refers to our ability to protect our data from those who are not authorized to view it. Confidentiality is a concept that may be implemented at many levels of a process. As an  example,  if we consider  the case of a person  withdrawing money from an ATM, the  person  in question will likely seek to maintain the confidentiality of the  personal  identification number (PIN)  that  allows him,  in combination with  his ATM card, to draw  funds  from  the  ATM. Additionally,  the owner  of the  ATM will hopefully maintain the confidentiality of the  account  number, balance,  and any other  information needed  to communicate to the bank  from which the funds  are being drawn. The bank will maintain the confidentiality of the transaction with  the ATM and  the  balance  change  in the account  after the funds  have been  withdrawn. If at any point  in the  transaction confidentiality is compromised, the results could  be bad  for the individual  the owner  of the ATM, and  the bank,  potentially resulting in what is known  in the information security field as a breach. 

Confidentiality can be compromised by the loss of a laptop containing data, a person  looking over our shoulder while we type a password,  an e-mail  attachment  being sent  to the  wrong  person,  an attacker  penetrating our  systems, or similar issues.