Answer:
It is a form of discrimination which is based on someone's chronological age. Many people use this term specifically to refer to discrimination against older people, but ageism can strike people of all ages. Like other forms of discrimination, ageism can be extremely harmful, especially when it is viewed as culturally normal and acceptable. Some countries have enacted anti-discriminatory laws against ageism, usually associating them with other hate crime motivations like racism, sexual orientation or religious intolerance.
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