The Seal Script (often called Small Seal Script) is the formal script of the Qin system of writing, the informal script of which was precursor to the Clerical Script. Seal script is the oldest style that continues to be widely practiced. Today, this ancient style of Chinese writing is used predominantly in seals, hence the English name. Although seals (name chops), which make a signature-like impression, are carved in wood, jade and other materials, the script itself was originally written with brush and ink on paper, just like all other scripts.
Most people today cannot read the seal script, so it is generally not used outside the fields of calligraphy and carved seals. However, because seals act like legal signatures in Chinese culture and (to a lesser extent in modern times) Japanese culture, and because vermillion seal impressions are a fundamental part of the presentation of works of art such as calligraphy and painting, seals and therefore seal script remain ubiquitous.