Complement pathways are part of the immune system that help the body fight infections. They consist of a series of proteins that work together to identify and eliminate pathogens like bacteria and viruses. There are three main pathways: the classical pathway, the lectin pathway, and the alternative pathway. Each pathway is activated differently but ultimately leads to the destruction of harmful invaders. When activated, complement proteins can enhance inflammation, promote phagocytosis, and form a membrane attack complex that directly destroys pathogens. This process is crucial for maintaining health and preventing infections, as it helps the body respond quickly to threats and clear away damaged cells.