As used in this article:

1. “Meeting” means the official convening of a public body for the purpose of conducting public business, including the use of videoconferencing for attendance and participation by the members of the public body.
2. “Public body” means any entity, for which a quorum is required in order to conduct public business and which consists of two or more members, performing a governmental function for the state or for an agency or department thereof, or for a public corporation as defined in section sixty-six of the general construction law, or committee or subcommittee or other similar body consisting of members of such public body, or an entity created or appointed to perform a necessary function in the decision-making process for which a quorum is required in order to conduct public business and which consists of two or more members. A necessary function in the decision-making process shall not include the provision of recommendations or guidance which is purely advisory and which does not require further action by the state or agency or department thereof or public corporation as defined in section sixty-six of the general construction law.
3. “Executive session” means that portion of a meeting not open to the general public.