Atta flour

Atta is an Indian wheat flour used to make most South Asian flatbreads, such as chapati, roti, naan and puri. Most atta is milled from hard wheat varieties, also known as durum wheat, that comprise 90% of the Indian wheat crop, and is more precisely called durum atta.

Hard wheats have a high gluten content, which provides elasticity, so doughs made out of atta flour are strong and can be rolled out very thin.

Atta is the Hindi or Urdu word for dough; it is used by metonymy to mean "flour used for baking". Atta refers to the pulverized whole wheat with brownish white color. In India and Pakistan a common term used for atta is "chakki atta" which is mostly used in rural areas. Chakki atta is ground wheat without any additions or subtractions, and is thus in more natural form. The word Chakki derives its meaning from traditional Indian way of grinding wheat in between two stone plates; modern day flour mills use stone crushers in the flour milling process.

In India and Pakistan wheat products like 'wheat powder' or 'wheat flour', 'atta flour', 'maida flour' and 'sooji' (semolina, also known as 'rava') are available in the market. There is technical difference between maida flour and sooji flour in terms of bran content; maida has negligible bran content. Maida flour is used mainly for making bhaturas and naan, types of Indian breads similar to roti or chapati, while sooji is used mainly in the preparation of a delight "kesari".

Whole wheat grains contain all three parts of the kernel (kernel means a grain or seed, as of a cereal grass, enclosed in a husk). There are, mainly, three parts for a wheat grain.

Kabir

The Atta flour found in commerce varies in fiber content from near 0% to 12%. Wholemeal (US whole wheat) atta is obtained from grinding complete wheat grains. It is creamy brown in color and quite coarse compared to other types of flour.

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Wikipedia