Lymphoma is a cancer of the lymphatic system, which is part of the body's immune network. It develops when lymphocytes, a type of white blood cell, grow and multiply uncontrollably. The disease is classified into Hodgkin lymphoma and non-Hodgkin lymphoma, each with distinct characteristics, symptoms, and treatment approaches. Lymphoma can affect lymph nodes, spleen, bone marrow, and other organs, and its progression and prognosis vary depending on the subtype and stage.