Need to know

The term "need to know", when used by government and other organizations (particularly those related to the military or espionage), describes the restriction of data which is considered very sensitive. Under need-to-know restrictions, even if one has all the necessary official approvals (such as a security clearance) to access certain information, one would not be given access to such information, or read into a clandestine operation, unless one has a specific need to know; that is, access to the information must be necessary for one to conduct one's official duties. This term also includes anyone that the people with the knowledge deemed necessary to share it with. As with most security mechanisms, the aim is to make it difficult for unauthorized access to occur, without inconveniencing legitimate access. Need-to-know also aims to discourage "browsing" of sensitive material by limiting access to the smallest possible number of people. The Battle of Normandy in 1944 is an example of a need-to-know restriction. Though thousands of military personnel were involved in planning the invasion, only a small number of them knew the entire scope of the operation; the rest were only informed of data needed to complete a small part of the plan. The same is true of the Trinity project, the first test of a nuclear weapon in 1945. Like other security measures, need to know can be misused by persons who wish to refuse others access to information they hold in an attempt to increase their personal power, prevent unwelcome review of their work, prevent embarrassment resulting from actions or thoughts. Need to know can also be invoked to hide extra-legal activities. This may be considered a necessary use, or a detrimental abuse of such a policy when considered from different perspectives. Need to know can be detrimental to workers' efficiency. Even when done in good faith, one might not be fully aware of who actually needs to know the information, resulting in inefficiencies as some people may be inevitably withheld information that they require to perform their duty.