Aquatint is an intaglio

Intaglio (printmaking)

Intaglio is a family of printmaking 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 or zinc plates are used as a surface, and the incisions are created by etching, engraving, drypoint, aquatint or...

 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...

 technique, a variant of 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...

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Intaglio printmaking makes marks on the matrix (in the case of aquatint, a copper or zinc plate) that are capable of holding ink. The inked plate is passed through a printing press

Printing press

A printing press is a device for applying pressure to an inked surface resting upon a print medium , thereby transferring the ink...

 together with a sheet of paper, resulting in a transfer of the ink to the paper. This can be repeated a number of times, depending on the particular technique.

Like 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...

, aquatint uses the application of acid to make the marks in the metal plate.