Impression
Each individual copy of a map is an impression. Also refers to the quality of the printing, as in "That's a nice impression."
Imprint
Printed data regarding the publisher, date of publication and place.
Intaglio
A printing process, whereby the metal plate was cut into using special tools or with the controlled use of acid. The incisions eventually produced the detail of the print. Various tones were created on the paper by the engraver's different incision depths, so that when the plate was ready for print, the whole surface was inked, then carefully rubbed into all the incisions, the deeper the ink the more ink will be in it, and thus the blacker the detail on the finished print.
All intaglio prints will have a plate mark.
