Emotional Intelligence (EI) is a pivotal concept for understanding human behavior and performance across diverse fields. Originally defined by Salovey and Mayer in 1990, EI refers to the ability to perceive, understand, regulate, and utilize emotions to guide thought and action. Over time, EI has gained recognition as a vital contributor to effective communication, leadership, collaboration, and resilience in areas such as education, healthcare, psychology, and business. This paper explores the evolution of EI and reviews three major theoretical frameworks: the skills model, which conceptualizes EI as a set of learnable cognitive abilities; the personality model, which treats EI as a stable personal trait; and the mixed model, which combines emotional competencies with personality factors. Each model offers unique approaches for assessing and applying EI in practical contexts. Distinct from traditional intelligence (IQ), EI provides valuable insights into emotional regulation, interpersonal relationships, and personal effectiveness. The study underscores EI’s multidimensional nature and emphasizes its increasing importance in academic research and professional practice.