🎥 PID
Proportional-Integral-Derivative — the tuning values that set how aggressively a flight controller corrects the drone back to the commanded attitude.
Too little PID feels loose/floaty; too much causes oscillation ("prop wash wobble").
What it actually does
PID is the control loop that keeps a quad doing what you asked. It compares where the aircraft is against where your sticks say it should be, and corrects — Proportional reacting to the current error, Integral to the accumulated error, Derivative to how fast the error is changing.
In practice
Raising P makes the aircraft respond more sharply but eventually oscillate. I holds attitude against steady forces such as wind. D damps the overshoot P causes and is the most sensitive to noise. Modern defaults fly well, so change one term at a time and fly the same pattern between changes.
Worth knowing
Fast oscillation usually means too much P or D, and hot motors after a short flight are a classic sign of a tune fighting itself. Land and check motor temperature after tuning changes.