This 'What is PID' video is the 3rd in the Closed loop system video series. This one introduces the PLC PID using a RSLogix 500 tutorial and pressure control system example of applying the PAC - PLC PID controller. You'll learn design of PID controller using PLC in the PID instruction ladder logic example basically the same as Studio 5000 PID instruction (example uses memory address instead of tags).

Now that you learned whats PID, if you want to learn PID controller tuning, see

https://bin95.com/Training_Software/PID_tuning_calculator_tips.htm