We've come a long way from using turtle shells to boil water and wrapping food in leaves to "roast it." The development of pottery allowed for the creation of fireproof cooking vessels with ceramic glazes making the porous container waterproof. There was a slow adoption of metal cookware due to the high production cost and there has been little development in cookware since.
By the 17th century it was common for a western kitchen to contain a number of skillets, baking pans, a kettle and several pots. In the American colonies these would be produced by a local blacksmith, while brass and copper vessels were common in Europe and Asia. Improvements in the 19th and 20th century allowed for pots and pans to be fashioned economically out of such metals as steel, stainless and aluminum.
Not many metals can be used for cookware, they must be able to conduct heat well, but they must be chemically unreactive so they do not alter the flavour of the food.
Uncoated aluminum can react with acidic foods and will change the taste. Anodized aluminum has a naturally occurring layer of aluminum oxide, which makes the surface hard and non-reactive. Cast iron cookware is slow to heat, but once at temperature provides even heating and can withstand very high temperatures. Since cast iron is porous it rusts easily so it requires seasoning before use and may require re-seasoning after many uses. Seasoning creates a thin layer of oxidized fat over the iron that protects it and renders it non-stick. Le Creuset developed enameled cast iron cookware in 1925. By firing two coats of enamel at 800°C the enamel becomes resistant to damage during normal use.
Copper provides the best thermal conductivity of common metals and therefore results in even heating. Copper is reactive with acidic foods. This was discovered with the introduction of tomatoes to the new world. Copper can be toxic and is generally lined with tin or more expensively with stainless. In some cases unlined copper is desirable, the making of meringues and foams, for example. Since copper is expensive and heavy it is now mainly incorporated into the construction of cookware, often as an enclosed heat-spreading disk.
Probably the most welcomed addition to the domestic kitchen are non-stick pans. In 1938 Teflon was invented (albeit accidentally) by a researcher at DuPont who was trying to develop a better refrigerant. In 1954 a French engineer devised a way to allow Teflon to adhere to aluminum and in 1956 the TEF(lon)AL(uminum) Company was started. Non-stick made cooking a dream, even the worst kitchen disasters cleaned up with little to no effort. Unfortunately since the early '80s there has been a litany of serious negative heath claims and Teflon has fallen out of favour.
In 2009 T-Fal (as it is known in North America) launched a line with an emphasis on health and the environment. They are PFOA (perfluoro-octanoic acid), lead and cadmium free, and the coating is recyclable.
Although new technologies in cookware will be developed, the current range of cookware will allow you to breathe easy (literally!), feel good about your purchase and have equipment to make any style of home cooking hassle-free. Non-stick fills a niche in our pot rack, somewhere between stainless steel and cast iron. Having a variety of purpose-built pans makes it more enjoyable to spend time in the kitchen, and by spending a little more time in the kitchen we are able to prepare healthier options for our families and eat less fast and processed foods, and anything that helps us save a little clean-up time is a welcome idea.