Intaglio is a family of printmaking

Printmaking

Printmaking is the process of making artworks by printing, normally on paper. Printmaking normally covers only the process of creating prints with an element of originality, rather than just being a photographic reproduction of a painting. Except in the case of monotyping, the process is capable...

 techniques in which the image is incised into a surface, known as the matrix or plate, and the incised line or area holds the ink. Normally, copper

Copper

Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...

 or zinc

Zinc

Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...

 plates are used as a surface, and the incisions are created by etching

Etching

Etching is the process of using strong acid or mordant to cut into the unprotected parts of a metal surface to create a design in intaglio in the metal...

, engraving

Engraving

Engraving is the practice of incising a design on to a hard, usually flat surface, by cutting grooves into it. The result may be a decorated object in itself, as when silver, gold, steel, or glass are engraved, or may provide an intaglio printing plate, of copper or another metal, for printing...

, drypoint

Drypoint

Drypoint is a printmaking technique of the intaglio family, in which an image is incised into a plate with a hard-pointed "needle" of sharp metal or diamond point. Traditionally the plate was copper, but now acetate, zinc, or plexiglas are also commonly used...

, aquatint

Aquatint

Aquatint is an intaglio printmaking technique, a variant of etching.Intaglio printmaking makes marks on the matrix that are capable of holding ink. The inked plate is passed through a printing press together with a sheet of paper, resulting in a transfer of the ink to the paper...

 or mezzotint

Mezzotint

Mezzotint is a printmaking process of the intaglio family, technically a drypoint method. It was the first tonal method to be used, enabling half-tones to be produced without using line- or dot-based techniques like hatching, cross-hatching or stipple...

. Collographs

Collography

Collagraphy is a printmaking process in which materials are applied to a rigid substrate . The word is derived from the Greek word koll or kolla, meaning glue and graph, meaning the activity of drawing.The plate can be intaglio-inked, inked with a roller or paintbrush, or some combination thereof...

 may also be printed as intaglio plates.
In the form of intaglio printing called etching, the plate is covered in a resin ground or an acid-resistant wax material.