Cell junctions are specialized structures that connect cells to one another, allowing them to communicate and maintain tissue integrity. There are several types of cell junctions, including tight junctions, adherens junctions, and gap junctions, each serving distinct functions in cellular organization and signaling. Tight junctions create a barrier that prevents the passage of substances between cells, while adherens junctions provide mechanical support by linking the cytoskeletons of adjacent cells. Gap junctions facilitate direct communication by allowing small molecules and ions to pass between cells, enabling coordinated responses in tissues such as heart muscle and nervous tissue.