A non disclosure agreement is also known as a confidentiality agreement.
It is a legal contract between two or more parties that outlines confidential materials , knowledge ,or information that the parties wish to share with one another for certain purposes , but wish to protect and restrict access to or by third party.
Simply, it is a contract in which the parties agree not to disclose information covered by the agreement to unauthorized persons.
Common examples of confidentiality agreement are doctor- patient , Attorney- client , bank – customers confidentiality. Again , employees may be required to sign a non disclosure agreement with the employer to protect trade secrets.
All in all , non disclosure agreements are used to protect secrets and access to information by third parties.