What are the three major processes used in printmaking?

In the visual arts, the techniques of printmaking are categorized into three major processes:1

• Relief: In this process, the non-printing areas of a block or plate are cut or etched away, leaving the design standing in relief to receive the ink. Common materials include wood and linoleum.23
• Intaglio: This is the opposite of relief printing, where the design is incised, scratched, or etched into the surface. Ink is applied into these grooves, and the plate is wiped clean; the image is then transferred to paper under high pressure, which forces the paper into the recessed lines.45
• Surface: These processes are defined by printing from a flat surface rather than from raised or recessed areas. This category is subdivided into planographic methods, such as lithography, and stencil methods.14

These methods are distinct in their approach to the printing surface, though they are sometimes combined to achieve specific artistic effects.13