As the printing of advertising material began to expand in the early nineteenth century, new and notionally more attention-grabbing letterforms became popular. Poster-size types began to be developed that were not merely magnified forms of book type, but very different and bolder. Some were developments of designs of the previous fifty years: ultra-bold types known as "fat faces", which were related to "Didone" text faces of the period but much bolder. Others had completely new structures: sans-serif letters, based on classical antiquity, and reverse-contrast letterforms. Some of the type designs appearing around this time may be based on signpainting and architectural lettering traditions, or vice versa.