B Cells are white blood cells in the lymphocyte class, and are part of the immune system in the body (Wikipedia). Similar to other white blood cells, B cells work to identify foreign invading objects; the B cell specifically recognizes antigens, or foreign protein strands. B cells are created to identify specific antigens, and are specialized so that the body can quickly and efficiently mount defenses. This specialization allows the body to adapt to new diseases; the B cell creates antibodies specific to the particular threat so that the threat can be eliminated without harming other cells or causing immune response problems. The B cells which identified a specific antigen become memory cells, replicating themselves to "remember" what the threat was and how to combat it; a reappearance of the same threat will be stopped faster and more efficiently, because the B cells are prepared for that specific antigen. B cells do not work to attack foreign cells directly; instead, their identification function works with the T Cells and other immune responses to allow the best reaction for a given threat.