The impression made after a seal is pressed in ink and then onto the image. Historically, seals have taken the place of [[signature]]s all across East Asia. The impression usually is rectangular or square, with the characters of the author's name in red ink.

For some examples, see "Wikipedia":[https://en.wikipedia.org/wiki/Seal_(East_Asia)] and "Wikicommons":[https://commons.wikimedia.org/wiki/Category:Chinese_seal_imprints].
印章