Cancer immunology concerned with the interaction of immune cells with the tumor cells which helps in understanding the commencement and development of cancer. Different types of therapies are developed accounting these interactions. All cancer cells have macro-molecules known as tumor associated antigens (TAAs) on their surfaces, which can be detected by our immune system. Cancer therapies can be catagorized into two types that is active and passive. In active therapy, immune system attack the cancer cells by targeting the TAAs but in passive therapy, lymphocytes, monoclonal antibodies and cytokines are used to enhance the anti-tumor responses