The first cookies were created by accident. The earliest cookie-style cakes are thought to date back to seventh-century Persia, one of the first countries to cultivate sugar. In the Netherlands, cooks used a small amount of cake batter to test their oven temperature before baking a large cake. These little test cakes were called "koekje", meaning "little cake" in Dutch.

Originally called "little cakes," cookies are made with sweet dough or batter, baked in single-sized servings and eaten out-of-hand. American cookies, like Americans themselves, have been a melting pot of cookie tastes and styles originating with the colonialists and thriving on waves of immigrant culinary contributions. Spice cookies, soft raisin cookies, shortbread, brown sugar-laced oatmeal, molasses and ginger drop cookies were delectably familiar. 

Today, cookies are most often classified by method of preparation - drop, molded, pressed, refrigerated, bar and rolled. There are different cookie styles, any of which can range from tender-crisp to soft. Their dominant ingredient, such as nut cookies, fruit cookies or chocolate cookies, can also classify them. Whether gourmet, soft or bite-sized cookies, new categories are always cropping up as the American appetite for cookies continues to grow.

There's nothing like eating a warm cookie freshly baked from the oven.

History: The first American cookie was originally brought to this country by the English, Scotch, and Dutch immigrants. Our simple "butter cookies" strongly resemble the English tea cakes and the Scotch shortbread.

In earlier American cookbooks, cookies were given no space of their own but were listed at the end of the the cake chapter. They were called by such names as "Jumbles," "Plunkets," and "Cry Babies." The names were extremely puzzling and whimsical.

Our ancestors favored oversized cookies (a must for hungry farm hands) and yesteryear's cookbooks yield countless receipts for traditional delights as Snickerdoodles, raisin-filled Hermits, Sand Tarts, and Jumbles, as well as all sorts of delectable butter cookies such as Southern-style Tea Cakes, and a myriad of sweet delicacies inspired by the Pennsylvania Dutch Mennonites, Amish, and Moravian communities. 

The Southern colonial housewife took great pride in her cookies, almost always called simply "tea cakes." These were often flavored with nothing more than the finest butter, sometimes with the addition of a few drops of rose water.

The cookie that broke the mold: Historians credit the innkeeper, Ruth Wakefield, with inventing what has since become an American classic - the chocolate chip cookie also known as the Toll House Cookie, so named after the inn in which it was served, was a hit. Around the 1930s something happened and this vast assortment of cookie-dom was supplanted by one infinitely important cookie that broke the mold - Tollhouse. As the story goes, a Massachusetts innkeeper ran out of nuts while making cookies. Therefore, she substituted a bar of baking chocolate, breaking it into pieces and adding the chunks of chocolate to the flour, butter and brown sugar dough.

Though they have evolved quite a bit since the Mayflower days, cookies have are never out of vogue. There are hundreds upon hundreds of cookie recipes in the United States. No one book could hold the recipes for all the various types of cookies. 

Perfect for snacking or as dessert, cookies today are consumed in 95.2 percent of U.S. households. Americans alone consume over 2 billion cookies a year, or 300 cookies for each person annually.

from http://www.kitchenproject.com/history/cookies.htm