A cookie (American English), or a biscuit (British English), is a baked or cooked snack or dessert that is typically small, flat and sweet. It usually contains flour, sugar, egg, and some type of oil, fat, or butter. It may include other ingredients such as raisins, oats, chocolate chips, nuts, etc.
Most English-speaking countries call crunchy cookies "biscuits", except for the United States and Canada, where "biscuit" refers to a type of quick bread. Chewier biscuits are sometimes called "cookies" even in the United Kingdom. Some cookies may also be named by their shape, such as date squares or bars.
Biscuit or cookie variants include sandwich biscuits, such as custard creams, Jammie Dodgers, Bourbons and Oreos, with marshmallow or jam filling and sometimes dipped in chocolate or another sweet coating. Cookies are often served with beverages such as milk, coffee or tea and sometimes dunked, an approach which releases more flavour from confections by dissolving the sugars, while also softening their texture. Factory-made cookies are sold in grocery stores, convenience stores and vending machines. Fresh-baked cookies are sold at bakeries and coffeehouses.
In many English-speaking countries outside North America, including the United Kingdom, the most common word for a crisp cookie is "biscuit". The term "cookie" is normally used to describe chewier ones. However, in many regions both terms are used. The container used to store cookies may be called a cookie jar.
In Scotland the term "cookie" is sometimes used to describe a plain bun.
Cookies that are baked as a solid layer on a sheet pan and then cut, rather than being baked as individual pieces, are called in British English bar cookies or traybakes.
The word cookie dates from at least 1701 in Scottish usage where the word meant "plain bun", rather than thin baked good, and so it is not certain whether it is the same word. From 1808, the word "cookie" is attested "...in the sense of "small, flat, sweet cake" in American English.