Hypertrophic cardiomyopathy (HCM) represents a phenotype of left ventricular hypertrophy unexplained by abnormal loading conditions. The definition is based on clinical criteria; however, there are numerous underlying etiologic factors. The MOGE(S) classification provides a standardized approach for multimodal characterization of HCM. HCM is associated with increased morbidity and mortality, and especially the assessment of the risk of sudden cardiac death is of paramount importance. In this review, we summarize essential knowledge and recently published data on clinical presentation, diagnosis, genetic analyses, differential diagnosis, prognosis, and treatment options that are necessary for understanding and management of HCM.