Facial expressions refer to the various movements and configurations of the face that convey emotions, attitudes, and intentions. This area of research focuses on understanding how different facial expressions are produced and interpreted, how they vary across cultures and individuals, and the role they play in social interactions and communication. Researchers study facial expressions using a variety of methods, including facial electromyography, facial recognition technology, and behavioral observations. Understanding facial expressions is important for fields such as psychology, sociology, and human-computer interaction.