There are three common approaches to defining confidential information: (1) using a system for identifying all confidential information; (2) list of categories of trade secrets; or (3) explicitly identify confidential information. Simple confidentiality agreement – This agreement is very simple and simple. It was designed primarily to be used by a person who wishes to disclose information that must be kept secret to another person. A confidentiality agreement (NDA), also known as a confidentiality agreement (CA), a confidential disclosure agreement (CDA), a protected information agreement (PIA) or a confidentiality agreement (SA), is a legal contract or part of a contract between at least two parties that describes documents, knowledge or confidential information that the parties wish to share for specific purposes. but restrict access.