Both professional bakers and home cooks rely on the same basic ingredients -- flour, sugar, fat, eggs, leaveners and salt. The quality and variety of these ingredients differ depending on whether you're cooking cakes, cookies, pies, yeast breads or quick breads. And the flavorings and added ingredients differ, too -- from chocolate to cherries to a combination of chocolate plus cherries.
Because baking relies on specific levels of heat surrounding food, check your oven's temperature with an oven thermometer to see if it's actually registering what it says it is. Ovens vary as much as 90 degrees Fahrenheit from the temperature you set, report food testers at Cook's Illustrated magazine.
Beginning with broken cereal grains in prehistoric times and evolving to ground grains that became flour for early humans around 10,000 B.C., flour remains one of the most essential ingredient in baking, But it's just one of the fundamental dry ingredients in baking.
The first and most fundamental wet ingredient in baking is water, which allows the yeast in yeast bread to get to work. Water or other wet ingredients provide the acids that baking powder and baking soda need to begin their chemical reactions, to dissolve sugars, blend ingredients and provide flavor.