A baguette is a long, thin loaf of French bread that is commonly made from basic lean dough (the dough, though not the shape, is defined by French law). It is distinguishable by its length and crisp crust.

A baguette has a diameter of about five or six cm (2-2⅓ in) and a usual length of about sixty-five cm (26 in), although a baguette can be up to one m (39 in) long. (extracted from Wikipedia)

Traditionally, French Baguette is made out of commercial yeast (Saccharomyces cerevisiae), although it varies within France from region to region. Sourdough Baguette is more common in the United States.