The review provides a comprehensive overview of the interaction between the innate and adaptive immune systems, emphasizing their synergistic roles in physiological and pathological contexts. The innate immune system, acting as the first line of defense, utilizes pattern recognition receptors to detect pathogens and initiate rapid responses. It includes barrier structures, effector molecules, and innate immune cells such as dendritic cells, granulocytes, monocytes, macrophages, natural killer (NK) cells, and innate lymphoid cells (ILCs). The adaptive immune system, on the other hand, provides highly specific and sustained killing of pathogens through B cells, T cells, and antibodies. The review highlights the complex interactions between these two systems, including the role of the cGAS-STING pathway in infections and cancers. It also discusses the importance of precise regulation of both systems in the fight against immune-related diseases. The paper concludes by summarizing current research breakthroughs and future directions in the field of immunity.The review provides a comprehensive overview of the interaction between the innate and adaptive immune systems, emphasizing their synergistic roles in physiological and pathological contexts. The innate immune system, acting as the first line of defense, utilizes pattern recognition receptors to detect pathogens and initiate rapid responses. It includes barrier structures, effector molecules, and innate immune cells such as dendritic cells, granulocytes, monocytes, macrophages, natural killer (NK) cells, and innate lymphoid cells (ILCs). The adaptive immune system, on the other hand, provides highly specific and sustained killing of pathogens through B cells, T cells, and antibodies. The review highlights the complex interactions between these two systems, including the role of the cGAS-STING pathway in infections and cancers. It also discusses the importance of precise regulation of both systems in the fight against immune-related diseases. The paper concludes by summarizing current research breakthroughs and future directions in the field of immunity.