Preppy is an upper-class American aesthetic out of Ivy League culture, built on polo shirts, khakis, and nautical influence, originating in northeastern prep schools across the 1950s and 60s as a marker of collegiate tradition and privilege. Polo shirts are the base. Chino pants or plaid skirts cover the bottoms. Blazers with crests go over the top. Loafers or boat shoes go below, with pearl necklaces and varsity-style layers.