Resistors are common elements of
electrical networks and electronic circuits and are
ubiquitous in electronic equipment. Practical resistors as
discrete components can be composed of various
compounds and forms. Resistors are also implemented
within integrated circuits. The electrical function of a
resistor is specified by its resistance: common
commercial resistors are manufactured over a range of
more than nine orders of magnitude. The nominal value
of the resistance will fall within a manufacturing
tolerance.