A bone marrow biopsy is a medical procedure primarily used to diagnose diseases affecting the bone marrow and blood, such as leukemia, anemia, and certain infections. It also plays a crucial role in the staging of lymphomas. During the procedure, a specialized needle is inserted into the bone, typically the hip bone, to collect two types of samples: a liquid sample (bone marrow aspirate), which contains bone marrow cells, and a small, solid piece of bone marrow tissue (bone marrow core biopsy), representing the spongy structure of the marrow.