The term 'century sections' refers to the divisions of a century into DECADES. A decade is a period of ten years, so a century is divided into ten DECADES. Each decade is further divided into two five-year periods, making a total of twenty sections in a century. DECADES are commonly used to refer to periods of time in history, such as the Roaring Twenties or the Swinging Sixties. They are also used to refer to specific age groups, such as the Baby Boomers or Generation X.