PID control, tuning, cascade control, ratio control, feedforward, override control, and sequencing/batch control — the control-theory core that everything else in this program is built to support.
Every module before this one — instrumentation, final control elements, PLCs, SCADA, HMI — exists to give a control loop something to measure and something to act through. This module is where those pieces come together into the actual control strategies running in a real plant: not just a single PID loop, but the cascade, ratio, feedforward, and override architectures engineers reach for when one PID loop by itself can't do the job fast enough, accurately enough, or safely enough.
By the end of this module you should be able to explain what each PID term actually contributes to loop behavior, why a cascade loop's secondary must run faster than its primary, when feedforward earns its added complexity over feedback alone, and how ISA-88's physical and procedural models let one reactor run three different recipes without three different PLC programs.