A non-disclosure agreement or more commonly known as a NDA. An NDA is a legal contract between (at least) two parties that outlines confidential material, knowledge, or information that the parties wish to share with one another for certain purposes, but wish to restrict access to or by third parties. NDAs are commonly signed when two companies, individuals, or other entities (such as partnerships, societies, etc.) are considering doing business and need to understand the processes used in each other’s business for the purpose of evaluating the potential business relationship. NDAs can be “mutual”, meaning both parties are restricted in their use of the materials provided, or they can restrict the use of material by a single party.