it is a condition called carpal tunnel syndrome. it is caused by compression of median nerve travelling through the carpal tunnel (at the wrist region), while you are working on computer (e.g typing), resulting in numbness of first three and the half fingers.
Normally copper is used in computer cables because it has one of the lowest resistance of all metals (resistance is how much the electrons scatter while travelling) Which makes it safer. And also it is very cheap. Aliminium is also used in cords but not as often:)
A computer sits on your lap while a notebook computer is generally smaller. I use the notebook computer because it is small and easy to use. Thank you for answering this question. I loved this question.