Ageism refers to discrimination and prejudice based on a person's age, affecting both younger and older individuals. Coined by Robert N. Butler in 1969, the term encompasses negative attitudes toward aging, discriminatory practices against older adults, and the oppression of younger people by older generations. Ageism manifests in various forms, including stereotypes that generalize abilities and interests based on age, a prejudice that leads to disdain or pity, and discrimination that results in harmful actions against individuals due to their age.