Americans eat cookies, the British eat biscuits.

A cookie is US English A biscuit is UK English for the same thing(An Oreo cookie for example is branded and sold as an Oreo biscuit) In the US, a biscuit is made from dough and is thick and chewy and often eaten with breakfast or dinner with gravy, it is not like a cookie or the UK biscuit US biscuit: A small, typically round cake of bread leavened with baking powder, baking soda, or sometimes yeast.

In the UK, a biscuit can be any type or brand. A cookie is a specific type of biscuit, the stereotypical flat American type with (or without) chocolate chips. In the US, a cookie is any type or brand - they use "cookie" as the British use "biscuit".

In the U.S. a cookie is a sweet desert. There are peanut butter cookies, chocolate chip cookies, sugar cookies, short breat cookies, etc. A biscuit is a bread you can put butter on and eat with your meal. A Cracker is a salted crisp wafer you can eat with cheese, plain, or with peanut butter, etc. All these terms are called something else in Britain.

The answers below are correct. But to add to the confusion, in British English, a cookie is a KIND of biscuit - the crumbly kind with chocolate chips in.