What demographic does the term teenager refer to?

The term "teenager" specifically refers to individuals who are aged 13 to 19 years old. This age range encompasses the period in a person's life commonly associated with adolescence, where significant physical, emotional, and social development occurs. The number "teen" in the term directly represents this age group, as all the years from 13 to 19 include the suffix '-teen.' This period is characterized by transitions from childhood into adulthood, and it encompasses significant milestones such as starting high school, experiencing puberty, and not infrequently, gaining more independence. Therefore, the definition aligns perfectly with the understanding of teenage years in various cultures and societies, confirming the choice that accurately identifies this age demographic.