Facial Expression Analysis is the study of how facial movements convey emotions and intentions. It involves examining features like the eyes, mouth, and eyebrows to interpret feelings such as happiness, sadness, anger, or surprise. This analysis can be performed manually by trained observers or through automated systems using algorithms and machine learning. This field has applications in various areas, including psychology, marketing, and human-computer interaction. For instance, emotion recognition software can enhance user experience in virtual reality or assist in customer service by understanding client emotions.