Ageism—bias based on age—pervades workplaces, healthcare, media and daily life, harming dignity and opportunity. It stereotypes older people as frail or obsolete and younger people as inexperienced, shaping hiring, pay and care, lowering self‑esteem and participation. Economically, it causes under‑employment, talent loss and higher welfare costs; socially, it breeds isolation and intergenerational tension. Combating ageism needs policy, inclusive cultures, accurate representation and everyday actions that recognise competence and worth at every age.