Additive Manufacturing File Format (AMFF) is a type of computer file that tells a 3D printer what to make. It contains instructions that tell the 3D printer which shapes, colors, and sizes to make for a 3D object. AMFF files are like a map that helps the 3D printer to make the right thing. It's like a recipe that tells the 3D printer what ingredients and measurements to use to build the 3D object.