Etching is a printmaking technique that involves using acid to carve designs into a metal plate, typically made of copper or zinc. The process begins with a coating of wax or resin on the plate, where the artist draws their design. The plate is then submerged in an acid bath, which eats away at the exposed metal, creating grooves that hold ink. Once the etching is complete, the plate is inked and wiped clean, leaving ink only in the grooves. Paper is then pressed onto the plate using a printing press, transferring the image. This method allows for intricate details and rich textures, making it a favored technique among artists like Rembrandt and Francisco Goya.