A sheriff is an elected law enforcement officer who is responsible for keeping order in a county. While police officers work for cities and towns, sheriffs oversee larger areas called counties, which often include small towns, rural areas, and unincorporated land where no city police force exists.

The sheriff leads a department of deputy sheriffs who patrol roads, investigate crimes, and respond to emergencies. In many counties, the sheriff also runs the county jail and provides security at courthouses. Because sheriffs are elected by voters rather than appointed, they answer directly to the citizens of their county.

In the Old West, sheriffs became legendary figures, sometimes the only law enforcement for hundreds of miles. A frontier sheriff might face bandits, settle disputes between ranchers, and maintain order in rough mining towns. Today's sheriffs use cars, computers, and radios instead of horses and telegraph lines, but they still serve as the primary law enforcement in many rural communities, where their counties might cover more land than some entire states back East.