For a deeper dive, I can recommend the Astrom and Murray book. It's free: http://www.cds.caltech.edu/~murray/amwiki/index.php?title=Second_Edition http://www.c

For a deeper dive, I can recommend the Astrom and Murray book. It's free: http://www.cds.caltech.edu/~murray/amwiki/index.php?title=Second_Edition http://www.cds.caltech.edu/~murray/amwiki/index.php?title=Se... This subject is tightly coupled with system modeling, and can touch many different domains: Cruise Control Bicycle Dynamics Operational Amplifier Circuits Computing Systems and Networks Atomic Force Microscopy Drug Administration Population Dynamics Cheap computers are making it easy to make controllers that can reliably control systems with hundreds or thousands of variables and unknown dynamics.