UV Coordinates (UV coordinates) is a technical term that is extremely important in rendering and optimizing game graphics (technical art). A two-dimensional positioning coordinate system represented by U (horizontal axis) and V (vertical axis) for pasting a 2D planar image (texture) onto the three-dimensional surface of a 3D model.
Real-world analogy: ``Wrapping paper with development diagram'' for wrapping boxes of caramel and chocolates
UV coordinates are "'gluing margins and coordinate positions (developed view)' of pre-printed wrapping paper to neatly wrap a three-dimensional candy box (3D model)". The horizontal direction is called "U (0-1)" and the vertical direction is called "V (0-1)" using special coordinate names. Thanks to the convention that ``prick the center point of (U=0.5, V=0.5) of the wrapping paper with a pin at this vertex,'' it is possible to paste a flat 2D illustration neatly and neatly without any deviation, even on a complex 3D face or body.
Illustration: UV Coordinates (UV coordinates) in Japanese notation
Detailed mechanism and operating principle
Use a DCC tool (such as Blender) to correctly unroll the model's UVs, or use the Shader Graph's "UV" node to dynamically control tiling, offset, and scroll animation.