What is a T cell?

T cells, or T lymphocytes, are a type of white blood cell that play a crucial role in the immune system. They help protect the body from infections and can recognize and destroy infected or cancerous cells. T cells are developed in the thymus gland and are essential for adaptive immunity, which tailors the body's immune response to specific pathogens. There are several types of T cells, including helper T cells, cytotoxic T cells, and regulatory T cells, each with specialized functions.