Lessons from the Modernist Poster

A poster has seconds to work. Modernist designers treated that constraint as a discipline, building compositions that could be read from across a street.
The tools were few: one dominant image or word, a strong contrast of scale, an asymmetric layout held together by an underlying grid, and generous empty space. Photography and sans-serif type replaced illustration and ornament.
The result was a visual language that felt objective and urgent at once. It influenced transit signage, concert posters and, eventually, the screen layouts we scroll through today.
To apply it now, ask what a viewer should understand in one second — then remove everything that competes with that.