Gaslighting is a psychological manipulation tactic where one person seeks to make another doubt their own perceptions, memories, or feelings. This often involves denying facts, twisting information, or presenting false narratives, leading the victim to feel confused and insecure about their reality. The term originates from the 1938 play "Gas Light," where a husband manipulates his wife into thinking she is losing her sanity. Gaslighting can occur in various relationships, including romantic partnerships, friendships, and even workplace dynamics, and can have serious emotional and mental health consequences for the victim.