I have been using Blender for few months on and off. I keep learning and forgetting how to do things. The problem is I don't have a solid understanding of few key things in blender especially about shaders, textures, and materials. I follow youtube tutorials to achieve my desired goal. There are people that will tell you what shader to use, but not why you should or should not use a different shader.
Could someone simply explain what are basics I should have in mind when setting the material for objects in general? Or could you please recommend a book or some online material that covers the basics on how to use shaders (in cycles), for instance at an intermediate level?