An operon is a cluster of genes in prokaryotic cells that are controlled together by a single regulatory mechanism. This means that when the operon is activated, all the genes within it are expressed simultaneously, allowing the cell to efficiently manage the production of proteins needed for specific functions, such as metabolism. Operons typically consist of a promoter, an operator, and one or more structural genes. The promoter is where RNA polymerase binds to initiate transcription, while the operator acts as a switch that can turn the operon on or off, depending on the presence of certain molecules, like repressors or activators.