FCOS full form

What does FCOS mean or stand for ?

Flight Computer Operating System is also known as a flight management system.This complex software is the heart of the flying machine.It is responsible for coordinating and integrating all the onboard systems like avionics,navigational controls, communications,autopilot etc . All modern day aircraft rely alot on the FCOS and after being airborne the plane basically flies itself with very little input from the pilots..