In digital control systems, the term "PID" stands for:

The term "PID" in digital control systems stands for Proportional, Integral, Derivative. This type of control algorithm is widely used in industrial control applications to maintain a desired setpoint by adjusting the control inputs based on the error, which is the difference between the desired setpoint and the process variable.

The proportional component responds to the current error value, providing an output that is proportional to the error. The integral component accounts for the accumulated error over time, correcting for any residual steady-state error that might occur. Finally, the derivative component predicts future error based on its rate of change, which helps to dampen the system’s response and improve stability.

This combination allows PID controllers to provide a robust method of achieving precise control in dynamic systems, making them a cornerstone of control engineering. Understanding this triad of components is essential for effective tuning and application in real-world systems.