Flatbread or Flat bread

Bread is an ancient food and the original form was likely flat.  The simplest formula is to make a dough based on  flour and water.  Flours are made from may crops: cereals such as wheat, maize, rice or rye; legumes such as peas, or lentils;  and starchy root vegetables such as potato, cassava,
A leavening agent,  from the Latin levare - to lift or raise, is used to entrain bubbles of a gas - such as carbon-dioxide - into the dough.   Adding living yeast,  which coverts starch into carbon-dioxide,  is a common leavening method.

Unleavened Flat Breads

Unleavened flat breads are arguably older recipes.   

Yufka , "saj bread" bread made on a saj pan. 

• Markook,  shrak,  also called sac ekmeği (saj bread) , or yufka,  in Turkish,  are made with a saj or tava , a large metal pan. Traditional village sac pans are large and convex facing up. They are mounted over a wood fire on stones, brick or metal frames.   The thin dough, also called yufka in Turkish, is similar to filo dough - see below.
• Roti -  also known as chapati, is made from atta flour - a whole wheat durum flour - and baked in a tandoor oven.   Paratha is a related bread.
• Paratha -    Paratha is made by using a roti dough and making layers by repeatedly coating with ghee and folding - creating a puff pastry effect.  Parathas can be filled with layers of potato or
  meat.
• Filo dough , called yufka  in Turkish,  is the base for many flat breads and pastries.  Filo (phyllo), leaf in Greek, is about as thin as a sheet of writing paper.   
• Börek is a class of filo-based pastries many of which can be considered flat breads.  
• Su böreği - 'water börek'  -  a thin filo-like dough (with eggs) is boiled briefly in large pans, A mixture of feta cheese, parsley and oil is scattered between the layers. The whole thing is brushed with butter and laid in a masonry oven to cook.
• Lavash - (Armenian) is soft, thin, unleavened flatbread baked in a tandoor oven.  It is common all over southwest Asia.  
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Leavened Flat Breads

• Bazlama -  is a Turkish, sourdough flatbread with a light yellow color.   A fermentation starter is added to the dough and it is left for a day to ferment .  It is baked on a hot plate. 
• Pita -  is a slightly leavened flat bread that puffs up during baking and forms a internal pocket. This is due to high oven temperature, thickness of the dough form, leavening, and moisture content. 
• Naan, or nan,  is a  leavened, oven-baked, south Asian bread.  Nan tends to be made from refined, white flour these days. Nan is traditionally baked in a tandoor.
• Sangak - from Persia,  based on whole-wheat flour,  is baked on a bed of small river stones in an oven.  
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