There’s good feeding and bad feeding.
Good food
Good food is the natural diet of the bird, reptile or mammal - for example, nectar, pollen, seeds and fruits of local native plants. Good food is provided in a balanced manner.
An excess of nectar-bearing plants can cause an increase in such species as Noisy Miners or Wattlebirds.
The best ‘good food’ is water. Provide water in sheltered spots in shallow dishes. Shallow pools on the ground will attract butterflies and may be used by reptiles.
Better than setting out food is providing habitat. Grow shrubs of varying heights in dense thickets. Grow groundcover plants and native grasses. See the article Fauna-Friendly Gardens for resources.
Bad food
Bad food is not part of animals’ natural diet - for example bread, meat scraps, fat, leftovers.
Bad food will mainly be eaten by vermin such as cockroaches, European Wasps, introduced birds such as Common Mynas, and by rats and mice.
Bad food, if eaten by native animals, can cause ill-health.
Remember, all feeding upsets nature’s balance. Feeding may cause an increase of bold animals, to the detriment of timid creatures.