It took a while for fast food to evolve into its most efficient form. Photos of fast food items over the years show the many different products and practices companies have developed, promoted, and scrapped along the way. Even fast food menu items have undergone dramatic changes. Certain products went out of style; people's food-buying habits shifted; and grocery stores started to sell new goods. The size and design of products also morphed over time as well. Older chains like Dairy Queen and McDonald's experienced many transformations since their initial launches. Old fast-food photos provide fascinating glimpses into the history of a distinctly American creation that now exists worldwide.