what u've said id absolutely correct...is hard to find a good teacher..and as u said this tech. is quite old so its not available in books and its hard to refer a good source for these erroneous topics. But the damn thing is that we are getting questions in our exam paper regarding this pmos..(not about its working but to draw Pmos inverter , nand and nor gates) . I can easily understand these Cmos and Nmos... but i hate these pmos questions...??????!!!!!