At present for most of the destinations, it is 20 to 25 kg for cargo and 6 to 7 kg for handbag per ticket but it does vary with the airline. For guest traveling to US at present baggage is controlled by Piece Concept. Under the Piece Concept, passengers are permitted per ticket to check two bags with a per-bag weight of up to 23 kg for Economy Class. Hand baggage of 7 kg is allowed for both international and internal flights.
(International airlines usually have different restrictions for carry-on luggage. Again, it is always best to check with your airline first to get their exact requirements).