Etching and engraving are both methods used to create detailed impressions on a surface. Etching uses a chemical reaction to create the impression, while engraving is a physical process of scratching the medium with a sharp tool.
Both methods are used in a type of printmaking called intaglio printing, which uses a carved metal sheet as a sort of stamp. Each metal sheet is a reusable template that can produce multiple prints. This method was an early way to create posters, propaganda, and art. Artists continued to develop the method of intaglio printing, discovering that selected dots and linework created intricate shading techniques.