Etching

Printing technique in which a metal plate is
first covered with an acid-resistant material, then
worked with an etching needle to create an intaglio
image. The exposed metal is eaten away in an acid
bath, creating depressed lines that are later inked for
printing. This technique was thought to have been
developed by Daniel Hopfer (1493-1536). Etching
surpassed engraving as the most popular graphic art
during the active years of Rembrandt and Hercules
Segher in the 17th century, and it remains one of the
most versatile and subtle printing techniques today