A technique found in 3D media that mimics the appearance of 2D illustrations.
A well-known example is The Legend of Zelda's Breath of the Wild.
In 3D media, cel rendering is typically employed by use of minimalist textures and shaders. This may include hard-edged shadows and highlights, sometimes to a degree that causes visual color banding, and other times, there may be an intentional omission of shadows altogether (e.g. Untitled Goose Game). There may also be use of a prominent outline (Okami), and on the flipside, there may be an omission of an outline altogether.
For the 2D cel shading technique, see anime coloring instead.
Anime
Videogames