Borderline Personality Disorder (BPD) is a significant psychological condition characterized by instability in relationships, self-image, emotions, and behaviors, often beginning in adolescence or early adulthood. Symptoms include intense emotions, fear of abandonment, impulsive actions, and potential self-harm, which can lead to difficulties in various areas of life. Although the exact causes are unclear, a combination of genetic and environmental factors may contribute, and effective treatments such as psychotherapy and medication can significantly help manage symptoms.