The textures and colors functionality is used to add colors and textures to your part. This can be useful to mark parts for machine specific manufacturing, to simulate painting, or to send the parts to a printer or service that can produce the real colors.
They are also used to visualize, define, and edit facegroups, groups of triangles that you wish to be handled as belonging together. For example, the cluster detection for supports generation can be controlled with facegroups.
Texture & Color is a module.