JAB and NUDGE are two terms used in the field of psychology. JAB is an acronym for Just A Bit, which is a type of behavior modification technique used to encourage positive behavior. NUDGE is an acronym for Nudging, which is a form of cognitive therapy that encourages people to make small changes in their behavior in order to achieve desired outcomes. PROD is an acronym for Proactive Directives, which is a type of behavior modification technique that involves providing direct instructions to individuals in order to help them reach their goals.