Biryani is the primary dish in a meal, while the pulao is usually a secondary accompaniment to a larger meal; In biryani, meat and rice are cooked separately before being layered and cooked together. Pulao is a single-pot dish: meat and rice are simmered in a liquid until the liquid is absorbed.
Both the biryani are same but the cooking style is different in dum biryani . Dum biryani is cooked by dum process, while other by normal process. Now the question arises, what is Dum cooking ? Here is the answer. Dum cooking. Par-cooked food is kept in Handi with minimal amount of water. The lid is placed and sealed with a paste of flour and water.
Calcutta/Kolkata biryani: This biryani mostly uses potatoes and eggs. It is much lighter spice wise, and only sometimes contains meat. The marinade is made of cinnamon, nutmeg, cloves, cardamom and other spices, and the rice is flavored with ketaki or rose water and yellow in color.
Rather than the regular Biryani, Sindhi Biryani is more spicy and tasty. Dont know whether it originates from Sindh or not. Just make sure about one thing if you dont want your rice overly cooked, keep on checking them while you r boiling them and drain them as soon as you turn off the heat.