The integral nonlinearity error (sometimes referred to as simply linearity error) is the deviation of the values on the actual transfer function from a straight line. This straight line can be either a best-fit straight line which is drawn so as to minimize these deviations or it can be a line drawn between the end points of the transfer function once the gain and offset errors have been compensated. The second method is called end-point linearity and is the usual definition adopted in data sheets.