Remove: With this button, you can remove the material from the
object. It won't erase the material. If it doesn't have any objects
assigned, Blender will purge the material the next time you exit the
software.
Duplicate: In some cases, you may want to create a new material
using another one as a template. With the duplicate button, you
can create a copy of the existing material.
Fake user: Any material that doesn't have an object assigned will
be at risk of deletion when you close Blender. You can enable the
Fake User to keep any material from getting purged, even if it
doesn't have any objects assigned.
Enable Nodes: Makes all information from a material to appear at
the Shader Editor using Nodes. Later in this chapter, we will learn
how to use Nodes.
Material list: All your materials will become part of the Blender file
you are working at the moment. Using this button lists all materials
available in this file, and you can easily reuse any of them. Instead
of creating new materials, you can select an object and pick one
from this list. The list is also useful to show materials that don't
have any objects assigned. You will see a zero right next to a
material that doesn't have any objects assigned.
Material index: We can have multiple materials in a single object
using indexes. Here you have a list of all materials assigned for
each index in the object.
Shader selector: Each material can use different shaders, and
you can select one from a list in this selector.