Secrecy

A secret is a piece of information that one person or a group of people know, and do not want others (either everyone, or certain people) to know. There are many reasons for keeping secrets. Some secrets are good (ones that should be kept secret like respect of citizen's privacy), others are bad (ones that ought not to be kept secret). Some things will only be kept secret until a certain time. Other things may be kept secret forever.

Sometimes things might be kept secret from someone because it is believed that it would upset them to know. Some things need to be kept secret for security reasons. If a person has a bank account they must keep their password secret. No one else should know it.

In businesses a lot of information is kept secret. This is usually called confidential. Things that are talked about at meetings are sometimes confidential. People who were at the meeting should not go telling everyone else what was discussed.

Another kind of secret is cryptographic secrets, which is short codes that unlock other secrets. That is, secrets protecting secrets and so forth.