One of a number of printings from the same plate. A term frequently used in qualitative descriptions of prints from earlier periods, before editioning was common, when an artist would experiment with the application and wiping of ink on the plate as they printed it to create tonal variances among prints produced from the same plate. In some cases, different types of paper could also be used to achieve different effects due to the manner in which the ink was absorbed by the paper. Today's master printers still create editions by hand however, impressions in an edition, when created, are virtually identical. Variances among impressions can also be due to damage or exposure to light and humidity.