The Chinese artistic craft traditionally used to make official name stamps and calligraphic seals is seal carving.
Seal carving involves cutting characters or designs into materials such as soapstone, jade, wood, or ivory. The finished seal is pressed into red paste and stamped on a painting, calligraphy, document, or object. A seal may identify the artist, owner, collector, office, or authority connected with a work.
Chinese seals can carry names, studio names, auspicious phrases, or institutional titles. The carved design may produce a red background with white characters or red characters against a white ground, depending on whether the marks are cut away or left in relief. Seals are therefore both functional objects and miniature works of calligraphy. They should not be confused with signatures: an artwork can contain several seals added by different owners over time.