The joining process originated in Germany. After the tiles are naturally pasted, a certain gap must be left, so as to ensure that the tiles will not be damaged or deformed due to extrusion due to thermal expansion and contraction. However, leaving seams sometimes seems particularly awkward, so people grope for the jointing process. Jointing is to fill the gaps between tiles with jointing materials, so that the tiles as a whole look better and more beautiful. Tile jointing is an indispensable link in modern decoration, and has even become an industry.