The Free On-line Dictionary of Computing (30 December 2018):
Programmable Interrupt Controller
    PIC A special-purpose integrated
   circuit that functions as an overall manager in an
   interrupt driven system.  It accepts requests from the
   peripheral equipment, determines which of the incoming
   requests is of the highest priority, ascertains whether the
   incoming request has a higher priority value than the level
   currently being serviced, and issues an interrupt to the CPU
   based on this determination.
   PICs typically have eight interrupt lines, and two PICs are
   often cascaded to provide 15 available interrupt lines.
   See also: Advanced Programmable Interrupt Controller.
   (2003-03-18)