What is "Pure Veg"?
Restaurants marked "Pure Veg" do not serve any meat, fish, or egg. This is to cater to strict dietary/religious requirements. It is excellent for vegans (though watch out for Ghee/Dairy).
Paneer: The King of Veg
Paneer (Cottage Cheese) is the default meat substitute. Try Palak Paneer (Spinach gravy) or Paneer Butter Masala.
Dal and Roti
The staple diet. Yellow Dal (Tadka) is lentil soup. Dal Makhani is black lentils cooked with butter and cream (rich and heavy).