Secrecy (also called clandestinity or furtiveness) 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. Secrecy by government entities is often decried as excessive or in promotion of poor operation; excessive revelation of information on individuals can conflict with virtues of privacy and confidentiality. It is often contrasted with social transparency.
Animals conceal the location of their den or nest from predators. Squirrels bury nuts, hiding them, and they try to remember their locations later.
Humans attempt to consciously conceal aspects of themselves from others due to shame, or from fear of violence, rejection, harassment, loss of acceptance, or loss of employment. Humans may also attempt to conceal aspects of their own self which they are not capable of incorporating psychologically into their conscious being. Families sometimes maintain "family secrets", obliging family members never to discuss disagreeable issues concerning the family with outsiders or sometimes even within the family. Many "family secrets" are maintained by using a mutually agreed-upon construct (an official family story) when speaking with outside members. Agreement to maintain the secret is often coerced through "shaming" and reference to family honor. The information may even be something as trivial as a recipe.
Secrets are sometimes kept to provide the pleasure of surprise. This includes keeping secret about a surprise party, not telling spoilers of a story, and avoiding exposure of a magic trick.