The main role of white blood cells (WBCs) in the human body is to protect against infections and diseases. They are a crucial component of the immune system, helping to identify and eliminate pathogens such as bacteria, viruses, and other foreign substances. There are various types of white blood cells, including neutrophils, lymphocytes, and monocytes, each with specific functions in immune responses. WBCs also play a role in inflammation and the body's healing processes. A healthy white blood cell count is essential for maintaining overall health and effective immune functionality.