Hematology is a department that specializes in the diagnosis and treatment of various diseases of the blood system. There are various diseases that can be seen in hematology, which are generally classified as follows: i. Red blood cell system diseases, including diseases caused by increased red blood cells, such as true erythrocytosis, primary thrombocytosis, and also various diseases caused by decreased red blood cells, such as iron deficiency anemia, aplastic anemia, autoimmune hemolytic anemia, thalassemia, paroxysmal sleep hemoglobinuria, bone marrow Proliferative abnormalities syndrome, etc. Various hematologic malignant diseases, such as acute leukemia, chronic leukemia, Hodgkin’s lymphoma, non-Hodgkin’s lymphoma, multiple myeloma, etc. Various bleeding disorders, such as allergic purpura, immune thrombocytopenic purpura, diffuse intravascular coagulation, vitamin K deficiency, hemophilia, etc.