The immunity comprises of a very complicated network of cells, tissues, and organs whose function it is to protect the body against attacks from external organisms causing infection or diseases. It’s primary purpose is to distinguish foreign invaders such as bacteria, virus, parasite, or whatever else from other cells in the body that are healthy.  

• The immune system can be divided into two main components:- he also classified immunity into two categories; the innate immune system and the adaptive immune system. The internal immune system comprises of immediate and nonspecific defensive reactions such as the skin barrier, the mucous membrane, neutrophils, and macrophages able to swallow and consume bugs.  
• However, the adaptive immune system is very specific and therefore needs some time to activate its defense. The mechanism depends on T and B cell immunity which has antigen recognition capability of pathogens’ components. These cells once activated produce instant and also persistent responses. The other types of white blood cells are the B cells that produce antibody and T cells which can either kill the infected cell or help others to carry out the process.  
• The adaptive immune system relies on memory that enables it to note past encounters with diseases. This is called immunological memory since the body will be better prepared with this information for a quicker response should the body encounter the same pathogen again.  
• This helps the body in combating diseases and aids in effective overall health. Some forms of health problem arise from disorders in the immune system, autoimmune, or immunodeficiency diseases. Well functioning immunity starts with proper nutritions, vaccination as well as other life style elements that you decide to follow.