A material defines the meaning of how it acts upon a mesh. For example, the 3ds Max Multi-material uses the material ID assigned to each mesh face as indices into its list of sub-materials. In this way, the user may assign several materials to a single mesh object. The Mesh class provides methods to get and set the material ID assigned to a face.

Materials are assigned to a mesh at the node level. There is one material assigned per node.

For more details see Working with Materials and Textures.