Leukemia is a group of malignant disorders that affect the blood and bone marrow. There are four main types classified as either acute or chronic based on cell maturity and disease onset. Acute leukemias like acute myeloid leukemia and acute lymphoblastic leukemia feature immature cells and a rapid progression. Chronic leukemias like chronic myeloid leukemia and chronic lymphocytic leukemia involve mature cells and a slower onset. Symptoms result from bone marrow failure and organ infiltration by leukemic cells. Diagnosis involves blood and bone marrow tests to identify the cell subtype and stage. Treatment aims to induce remission through chemotherapy with curative intent, including induction, consolidation, and maintenance therapies and sometimes stem cell transplantation.