I just downloaded the very nice tutorial on The Hypershade available at www.mtmckinley.net
Thanks again for the valuable indication.
I've learnt from this overview on the Hypershade that the three default material nodes should never be modified. Now, I would like to understand if any modifications to these materials nodes are permanent within Maya or if, as I believe, they only affect your current scene and are basically turned back to their default values if you restart Maya and get ahead with another project...
The reason for this question is that I have, in fact, modified the Lambert1 node. Now I understand why any new primitive (created in scene I'm working on) was automatically mapped with a texture assigned to another object.
I think everything should be back to normality now... thanks to the information received from this tut. However, I would like to make sure that my Lambert1 node in Maya is indeed set up with perfect adherence to its default values... Could you shed some light on this please? I really hope the modifications applied to the default material nodes are not permanent... if so, could you please confirm the original attributes of the Lambert1 node?