Hematology is the study of blood and blood-forming organs, covering both the diagnosis and treatment of blood-related disorders. These disorders can affect red blood cells (like anemia and sickle cell disease), white blood cells (like leukemia), platelets (like thrombocytopenia), and plasma components (like hemophilia). A hematologist is a doctor who specializes in this field, with some focusing specifically on hematologic malignancies (blood cancers)