Hematological malignancies are cancers that affect the blood, bone marrow, and lymphatic system. Common types include leukemia, lymphoma, and myeloma. These conditions arise from the uncontrolled growth of blood cells, leading to various symptoms such as fatigue, infections, and bleeding. Diagnosis typically involves blood tests, bone marrow biopsies, and imaging studies. Treatment options may include chemotherapy, radiation therapy, and stem cell transplants. Early detection and appropriate management are crucial for improving outcomes in patients with hematological malignancies.