Cell-cell interactions refer to the complex communication and signaling processes that occur between individual cells within a multicellular organism. These interactions are crucial for maintaining cellular homeostasis, coordinating cell behavior and functions, and regulating various physiological processes such as embryonic development, immune responses, and tissue repair. Cell-cell interactions can involve direct physical contacts between neighboring cells through special membrane-bound structures called gap junctions or adherens junctions. They can also occur through soluble signaling molecules such as hormones, cytokines, and growth factors that are secreted by one cell and received by another cell through cell surface receptors. Research in the area of cell-cell interactions focuses on understanding the mechanisms and molecular pathways involved in these communication processes, as well as their role in normal cellular function and disease states. This research has important implications for various areas of biology and medicine, including cancer biology, immunology, neurobiology, and regenerative medicine.