Strictly speaking hand baggage allowances are limited to one bag that should be smaller than a certain size (dimensions will be on the airlines website). Usually hand baggage allowances are 7 - 10 Kg, I can't remember what Qatar's was. However, they told me that they do not weigh a laptop as part of the hand baggage allowance.
The strange thing with hand baggage is that you are limited to one bag at the check in, but as soon as you get airside you can shop to your hearts content in the duty free area and take another 10 carrier bags full of shopping on to the aircraft
