The Korea gallery on the first floor of the ROM has a plexiglass tray with 22 small black cubes, each about the size of a little fingertip. In the dim light, it's hard to tell what they are.
These humble little objects represent one of the great innovations of the past millennium: movable type. They are small metal blocks with Chinese characters cast on one side.
When a page is to be printed, a typesetter arranges the characters in a frame, applies ink, and presses the paper against the frame. Behind the trays of type displayed printed plates. The rectangular frame is approximately 27cm high and 43cm wide and has two vertical wooden handles on either side.
Printing was invented by Bi Sheng around 1045. First, clay and wood were used, and later copper and tin were used. To be honest, printing Chinese characters with movable type is quite tiring because there are so many characters comparing to 26 letters in English. So smart Chinese used metal movable type on banknotes with a small number of characters. The Shanghai Museum has a copper plate of the "Zhenyou Baojuan" of the Jin Dynasty in 1215. According to research, the Jin Dynasty began to print copper-plate banknotes in 1154, and the Northern Song Dynasty used copper-plate movable type banknotes to print banknotes earlier than the Jin Dynasty. However, there are no physical objects from the Northern Song Dynasty earlier than 1154. The earliest surviving Northern Song Dynasty banknotes are printed in 1161.
Later, metal movable type was introduced to Korea, and they worked tirelessly to print books. "Jikji " printed by Muxingde Temple in Qingzhou in 1377 was recognized by UNESCO in 2001 as the oldest extant metal movable type book in the world, and was thus registered in UNESCO Memory of the World.
To answer the question, the movable type printing was invented by the Chinese, and metal movable type was also used first in China. But Korea used this technology to print a book first.