Trademark distinctiveness both concepts, see Apple Corps and its disputes with Apple, Inc. If a court rules that a trademark has become "generic" through common use (such that the mark no longer performs the essential trademark function and the average consumer no longer considers that exclusive rights attach to it), the corresponding registration may also be ruled invalid. For example, the Bayer company's trademark "Aspirin" has been ruled generic in the United States, so other companies may use that name for acetylsalicylic acid as well (although it is still a trademark in Canada). Xerox for photocopiers and Band-Aid for adhesive bandages are
Hippocrates of Chios geometry textbook for many centuries. Hippocrates is believed to have originated the use of letters to refer to the geometric points and figures in a proposition, e.g., "triangle ABC" for a triangle with vertices at points A, B, and C. Two other contributions by Hippocrates in the field of mathematics are noteworthy. He found a way to tackle the problem of 'duplication of the cube', that is, the problem of how to construct a cube root. Like the quadrature of the circle this was another of the so-called three great mathematical problems of antiquity. Hippocrates also invented the technique of