Abscissa and ordinate is the distance between the projection and the origin of the axis, and whose sign is given by the location on the projection relative to the origin (before: negative; after: positive). Usually these are the horizontal and vertical coordinates of a point in a two-dimensional rectangular Cartesian coordinate system. The terms can also refer to the horizontal and vertical axes respectively (typically "x"-axis and "y"–axis) of a two-dimensional graph. An ordered pair consists of two terms—the abscissa (horizontal, usually "x") and the ordinate (vertical, usually "y")—which define the location of a point in two-dimensional rectangular space. Though the word "abscissa"
Bit-paired keyboard from ' to *. An important subtlety is that ASCII was based on mechanical typewriters, but electric typewriters became popular during the same period that ASCII was adopted, and made their own changes to layout. Thus differences between bit-paired and (electric) typewriter-paired keyboards are due to the differences of both of these from earlier mechanical typewriters. Bit-paired keyboards were common in the United States in the 1960s and 1970s, due to ease of manufacture, but died out in the late 1970s with office automation, due to the number of users already accustomed to (electric) typewriter layouts. Bit-paired keyboard layouts survive