John Alcorn was born in 1935, in Corona, Long Island, and lived most of his childhood in Great Neck Long Island. When he enrolled as a student at the Cooper Union, he intended to be an architect, but he gradually became interested in graphic arts. Inspired by some very fine teachers like the painter Robert Gwathmey and the designer Jerome Kuhl, the young Alcorn studied drawing, calligraphy, the mechanics of typography, dimensional design, illustration, graphics and advertising design.

After graduating in 1955, Alcorn married Phyllis. He started working in the art department of Esquire Magazine and in the pharmaceutical sector for the agency William Douglas McAdams. In spring 1956 he was hired by Push Pin Studios, the celebrated studio founded two years earlier by former Cooper Union students Milton Glaser, Seymour Chwast, Reynold Ruffins and Edward Sorel, a daring group of artists that succeeded in blurring the line between fine art and commercial art.

In late ’58, he joined CBS Radio and subsequently CBS-TV art department, where he worked with designer Lou Dorfsman, who praised Alcorn for his extraordinary capacity for combining illustration and design and taught him the keys of the most effective advertising communication. Having mastered his skills, in 1961 he decided to launch himself once and for all as a freelancer.