Editing Secrecy (section)

{{Short description|Practice of hiding information to certain individual or group for personal or interpersonal reason}}
{{other uses}}
{{hatnote|Several terms redirect here. For other uses, see [[Covert (disambiguation)]], [[Secret (disambiguation)]], and [[Secrets (disambiguation)]].}}
{{Redirect-distinguish-for|Clandestinity|Clandestinity (Catholic canon law)||Clandestine (disambiguation){{!}}Clandestine}}
[[File:If you talk too much, this man may die.jpg|thumb|U.S. soldier at camp during [[World War II]]]]
[[File:Loose lips might sink ships.jpg|thumb|upright|[[Loose lips might sink ships]], World War II slogan]]
'''Secrecy''' is the practice of hiding information from certain individuals or groups who do not have the "need to know", perhaps while sharing it with other individuals. That which is kept hidden is known as the secret.

Secrecy is often controversial, depending on the content or nature of the secret, the group or people keeping the secret, and the motivation for secrecy.
[[File:Premier-secret-confie-a-Venus.jpg|thumb|upright|''First secret confidence to Venus'', [[François Jouffroy]]]]
Secrecy by government entities is often decried as excessive or in promotion of poor operation{{by whom|date=March 2015}}; excessive revelation of information on individuals can conflict with virtues of [[privacy]] and [[confidentiality]]. It is often contrasted with [[Transparency (social)|social transparency]].
[[File:Un_Secret_d'en_haut.jpg|thumb|upright|''A Secret from on High (Secret d'en haut)'', [[Hippolyte Moulin]] (Hypolite Moulin), 1879]]
[[File:Burnbag Obama Biden.jpg|thumb|A [[burn bag]] and [[classified information|security classification]] stickers on a [[laptop computer|laptop]], between [[President of the United States|U.S.President]] [[Barack Obama]] and [[Vice President of the United States|Vice President]] [[Joe Biden]], May 1, 2011]]

Secrecy can exist in a number of different ways: encoding or [[encryption]] (where mathematical and technical strategies are used to hide messages), true secrecy (where restrictions are put upon those who take part of the message, such as through [[Classified information|government security classification]]){{Citation needed|date=April 2018}} and [[obfuscation]], where secrets are hidden in plain sight behind complex idiosyncratic language ([[jargon]]) or [[steganography]].

Another classification proposed by [[Claude Shannon]] in 1948 reads that there are three systems of secrecy within communication:<ref>{{Cite journal|last=Shannon|first=C.E.|date=1946–1948|title=Communication Theory of Secrecy Systems|url=http://www.ugr.es/~aquiran/cripto/museo/shannon1949.pdf|pages=1}}</ref>
# Concealment systems, including such methods as invisible ink, concealing a message in a harmless text in a fake covering cryptogram, or other methods in which the existence of the message is concealed from the enemy.
# Privacy systems, for example, [[voice inversion]], is a special equipment required to recover the message.
# "True" secrecy systems where the meaning of the message is concealed by the cypher, code, etc. Although, its existence is not hidden. The enemy is assumed to have any special equipment necessary to intercept and record the transmitted signal.