G-protein-coupled receptors (GPCRs) are a large family of membrane proteins involved in signal transduction. They are one of the most important classes of drug targets in pharmacology, as they play a key role in regulating numerous physiological processes in the body. GPCRs are found on the surface of cells and are involved in transmitting signals from the extracellular environment to the inside of the cell. When a ligand, such as a hormone or neurotransmitter, binds to a GPCR, it triggers a series of molecular events that ultimately lead to a cellular response. Research in the area of GPCRs focuses on understanding the structure and function of these receptors, as well as their role in disease processes. This research aims to develop new drugs that can either activate or inhibit GPCRs, in order to treat a wide range of conditions including cardiovascular diseases, cancer, and neurological disorders.