Hello there, my name is Dr. C. Monster. I am the world's foremost expert on cookies and today I'd like to share my knowledge with you.
Cookies are baked items, consisting of eggs, sugar, fat, and add-ins for desired flavor. This recipe can be modified as desired but this is the most common form, today at least. Cookies are similar to cakes in that they are both pastries. What separates a cookie from a cake is that cakes use water to form the batter, as this allows bubbles to form better and results in fluffy texture. Cookies use oil as the cohesive medium in batter and this results in a more solid, chewy pastry, much flatter and more condensed than a cake. Oils, whether they be in the form of butter, egg yolks, vegetable oils or lard are much more viscous than water and evaporate freely at a much higher temperature than water. Thus a cake made with butter or eggs instead of water is far denser after removal from the oven.
Oils in baked cakes do not behave as soda in the finished result. Rather than evaporating and thickening the mixture, they remain, saturating the bubbles of escaped gases from what little water there might have been in the eggs, if added, and the Co2 released by heating the baking powder. This saturation produces the most texturally attractive feature of the cookie, and indeed all fried foods: crispness saturated with a moisture (namely oil) that does not sink into it.
Cookies have been around for as long as written cookbooks, though they did not exist in the form we know them today. For starters, they were not always sweet, indeed they were most likely very savory and meant for sustenance on long journeys, not for pigging out in front of the TV.
Cookies were created in Persia, shortly after sugar became common in the region. Cookies Spread to Europe when the Muslims conquered Spain. Their popularity caught on fast, and in 700 short years were available to all levels of society and were one of the first foods sold out of a cart. Cookies came to America with the Dutch in the 1600s. The Dutch called them "Koekjes" and we bastardized that into Cookie. Today, they have become one of the most popular junk foods and some Cookieologists, such as myself, predict that Americans are slowly turning into cookie dough, and will make some delicious cookies when baked
The first iterations of cookies would be considered disgusting by today's standards. The first cookie was most likely a Jumble cookie, made from nuts, sweeteners, and water
These were what travelers ate on long journeys, they kept well and were easy to store. They also provided a good source of energy and were very similar to granola bars, except that they were not consumed by pretentious douchetards.
There are many different classes of cookies, each with their own method of preparation, fillings, and origins.
Drop Cookies: These are the most well known and beloved of all cookies because they include the Chocolate Chip cookie. They also include Oatmeal cookies and the Redheaded stepchild of cookiedom, the Oatmeal Raisin Cookie.
These cookies are made by dropping (hence the name) soft dough into clumps on a cookie sheet baking them until golden brown.
Refrigerator cookies: These are the cookies from a tube.
Just slice the dough log up and cook the slices. These are good cookies, but they lack the love and care that homemade cookies ooze with. (Though they keep the fat that all good cookies ooze with).
Molded Cookies: These are cookies made from a much stiffer dough and include such favorite as the Snickerdoodle and the only cookie that can kill you, The Peanut Butter Cookie.
These cookies are reffered to as molded because they are crafted a certain way. Snickerdoodles have ridges and valleys in them to ensure even baking and peanut butter cookies have fork lines pressed into them for the same purpose.
Rolled Cookies: These cookies are also made from sitff dough, rolled out and cut into shapes. These are your christmas cookies and gingerbread men cookies.
Pressed Cookies: These are cookies that kind of look like turds. They are made from extruding dough from a cookie press before decorating them. The most common variety of this cookie is the Spritzgeback.
Bar Cookies: These are things like Brownies, Rice Krispie Treats, and any other baked good made in a tray with oil or something other than water as their constituency medium.
Sandwich Cookies: This cookie sees two wafers sandwiching a filling, usually marshmallow, jam, or peanut butter. The best, most well-known, and only one worth mentioning is the Oreo.
In the UK, they call cookies biscuits, but fuck them, a cookie is sweet and a biscuit is a glorified grease napkin you can eat. They also make shortbread cookies which are god-awful.
Japan gave us fortune cookies, which are ok-tasting and contain humorous advice. Not bad, but not the most impressive thing to come out of japan.