Every day, millions of vehicles move through cities without bringing them to a complete standstill. Behind every green light, highway ramp, traffic camera, and electronic road sign is an invisible network constantly monitoring conditions, adjusting signals, and directing traffic to keep people and goods moving. Most drivers never notice it—but without it, modern cities would quickly grind to a halt.

In this episode, we explore the secret traffic system that keeps cities from locking up. We dive into transportation engineering, civil engineering, computer science, electrical engineering, traffic operations, and intelligent transportation systems to understand how engineers manage the movement of millions of vehicles every day.

We examine synchronized traffic lights, adaptive signal control, traffic sensors, inductive loop detectors, ra ...