Hi all! I started my first control engineering course this semester. There are some terms that confused me. I am now learning closed-loop systems. And the lecturer was discussing the reduced sensiticity to process disturbance and load variation of a closed-loop system when compared to a open-loop system. But I am confused by the terms "load variation" and "process disturbance"... Basically, what is a "load"? I was dealing with some input signal and output signal, and what role a "load" plays in a system? To childish me, "load" is something that a system need to bare or withstand.... Please help.