Here's a little more detail:

* Bone marrow is the spongy tissue found inside the bones. It's like a factory for blood cells, including red blood cells, platelets, and white blood cells.

* Stem cells within the bone marrow are responsible for creating all the different types of blood cells. These stem cells can differentiate and develop into the various white blood cells we need to fight infections.

While the bone marrow is the primary site of production, some white blood cells, like lymphocytes, can mature and develop in other parts of the body, such as the lymph nodes, spleen, and thymus.