Here to all, these are some of the knowledge on flour. 

Plain Flour- All purposed Flour

Self Raising Flour – Plain Flour + Baking Powder added

Cake Flour – Lower Protein than Plain Flour

Cake Flour, Get 80% of Plain Flour + 20% of Cornstarch (Eg: 80g of Plain Flour + 20g of Cornstarch Flour = 100% of Cake Flour)

Wheat Flour is the only flour and grain to form a strong, cohesive dough that will retain gas and produce light baked goods

Tips: Cake Flour give Muffins/Cakes a finer texture