When traveling as a backpacker you shouldn’t go around with piles of cash to cover 6 or 12 months expenses in your bag. Luckily the world is adjusting to other forms of exchange than paper money, and the plastic cards seems to offer the perfect solution to this problem.
Always bring at least two plastic cards with you - for example, a Visa and a Master Card. Bring your bank's "express/emergency" service phone number with you, in case your credit card is stolen or lost. Keep your phone numbers separated from your cards.