T cells are a crucial type of white blood cell central to adaptive immunity, the body's system for customizing defenses against specific pathogens. These cells act like soldiers, identifying and eliminating targeted invaders. Immature T cells, known as T-stem cells, travel to the thymus in the neck, where they mature and develop into different kinds of T cells. They become active in the immune system under the influence of thymosin and other factors. During maturation, T cells that might mistakenly attack the body's own tissues are typically destroyed or suppressed.There are various types of mature T cells, though not all their functions are understood. T cells can release cytokines, such as interleukins, which further enhance the immune response. The activation of T cells is often evaluated to gauge the health of patients with specific conditions and less commonly with other disorders. T cells are also referred to as T lymphocytes, with the "T" representing "thymus," the organ where they mature, unlike B cells, which mature in a different location.