A bistro or bistrot /ˈbiːstroʊ/, is, in its original Parisian incarnation, a small restaurant, serving moderately priced simple meals in a modest setting. Bistros are defined mostly by the foods they serve. French home-style cooking, and slow-cooked foods like cassoulet, a bean stew, are typical.
Bistros likely developed out of the basement kitchens of Parisian apartments where tenants paid for both room and board. Landlords could supplement their income by opening their kitchen to the paying public. Menus were built around foods that were simple, could be prepared in quantity and would keep over time. Wine and coffee were also served.
The word derived from the Russian bystro (быстро), "quickly". It entered the French language during the Battle of Paris (1814). Russian officers or cossacks who wanted to be served quickly would shout "bystro".