* The word 'Roti' is used commonly in north, central and east India, whereas 'Chapati' is used more in west (Mumbai), and south India. Only in south India Chapati is fried in a bit of oil! Elsewhere, only a Paratha is fried with oil or ghee * Chapati is also made of plain white flour (maida or all purpose flour) in some places in south India.
Sheermal is a mildly sweet naan made out of maida, leavened with yeast, baked in a tandoor or oven. Sheermal was traditionally made like roti. Today, sheermal is prepared like naan. The warm water in the recipe for naan roti was replaced with warm milk sweetened with sugar and flavored with saffron and cardamom. The final product resembles Danish pastry.
Tandoori rotis require a special type of oven, called a tandoor, predominantly found at restaurants. It is not common for a housewife to have a tandoor. Both are made of flour, but chapati is made of whole wheat flour, while tandoor roti is made of maida, or white all-purpose flour.