Clerical script (lishu, 隸書) evolved toward the end of the first millennium BC and remained in common use through the Han dynasty (206 BC–AD 220). As its name implies, clerical script was frequently used in preparing official records and documents, and it was utilized for both public monuments and private correspondence. This simplified variation of seal script plays upon the use of brush and ink. Modulated and tapered strokes, as well as distinct downward sweeping strokes, are considerably more prominent than the more balanced strokes of seal script, which reflect the use of stiff writing implements.