Cups, Crocks and Bottles need to be appropriately sized for your bird and bird cage.  The food and water dishes need to be easy to remove and clean since this needs to be done on a daily basis.  Those made out of stainless steel, crockery, or high-impact plastics are able to withstand the washing and disinfecting necessary to maintain the health of your feathered friend. Water may be given in a dish or in a water bottle such as the type guinea pigs or hamsters use.  Make sure your bird knows how to use the bottle and that it is easy to remove, wash, and refill.  Use a bottle brush for cleaning it.  Locate food and water dishes where they will not be contaminated with droppings. Having an extra set of dishes makes cleaning and feeding a little easier.