Toast is sliced bread that has been browned by radiant heat. The browning is the result of a Maillard reaction altering the flavor of the bread and making it firmer. The firm surface is easier to spread toppings on and the warmth can help butter reach its melting point. Toasting is a common method of making stale bread more palatable. Bread is commonly toasted using a toaster or a toaster oven. Toast may contain acrylamide caused by the browning process, which is suspected to be a carcinogen. However, claims that acrylamide in burnt toast causes cancer have not been proven.

Bread is a staple food prepared from a dough of flour and water, usually by baking. Throughout recorded history and around the world, it has been an important part of many cultures' diet. It is one of the oldest human-made foods, having been of significance since the dawn of agriculture, and plays an essential role in both religious rituals and secular culture.