Managing Cycles Materials - Blender Cycles Materials and Textures - page 72

5. In the Properties subpanel right below the Color subpanel, we can change the size

of the label name, which is set to 20 by default, and by unchecking the Shrink item,
we can freely resize the frame bigger, which otherwise encloses the nodes with a
fixed boundary (the default setting), which is shown in the following screenshot for
your reference:

The Frame with label and color

Linking materials and node groups

Similar to Blender Internal, Cycles materials can be linked from libraries. Every blend file
containing linkable assets can be a library.

Linking materials is really useful practice. Let's say you have 20 different blend files with
objects using an iron shader, and at a certain point of your workflow, you need to modify
this iron material in all the files. By having this material linked in all the 20 files from a
single blend, it is possible to update all of them at once by modifying just one shader in the
library file (as you know, a linked material reflects the properties of the library material and
cannot be edited, differently from an appended material that is local to the file where it has
been imported from the library file).