Almost everyone knows this but just to be clear: a bagel is a round holey bread roll.
They usually have a brown color and a glazed sheen regardless of their appearance. The bread has a satisfying firm chewiness when you bite into it.
During baking the dough is boiled for 60-90 seconds to achieve a glazed appearance.
Among the ingredients in the water are lye (also known as caustic soda or sodium hydroxide) barley malt syrup honey or baking soda.
It is this process that gives the bread its distinctive look flavor and chewiness.
In spite of the fact that spellings vary by country (beigel/baygal etc. ) the root word originates from the German beugel meaning bracelet.