Receptor signaling is a biological process where cells communicate with each other through specific proteins called receptors. These receptors are located on the cell surface or within the cell and bind to signaling molecules, such as hormones or neurotransmitters. When a signaling molecule attaches to a receptor, it triggers a series of events inside the cell, leading to a response, such as changes in gene expression or cell behavior. This process is crucial for various physiological functions, including immune responses, nervous system signaling, and metabolism. Proper receptor signaling ensures that cells respond appropriately to their environment, maintaining homeostasis and overall health. Disruptions in this signaling can lead to diseases, including cancer and diabetes.