The primary function of white blood cells (WBCs), or leukocytes, is to protect the body against infections and foreign invaders, such as bacteria, viruses, and parasites. These cells are a crucial component of the immune system, working to identify, attack, and eliminate pathogens. There are several types of white blood cells, each with specific roles. For instance, neutrophils are typically among the first responders to infections, while lymphocytes are essential for adaptive immunity, producing antibodies. White blood cells also play a role in inflammatory responses and can remember past infections, allowing for quicker responses to previously encountered pathogens.