Emotional intelligence (EI) is the ability to recognize and manage one's own emotions as well as the emotions of others, with a significant impact on personal and professional success. It encompasses several models, including Goleman's constructs of self-awareness, self-management, social awareness, and relationship management, as well as Bar-On's focus on intrapersonal and interpersonal skills. Developing EI involves techniques such as self-evaluation, managing emotions, and adapting behaviors to improve interactions and career outcomes.