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Technology

Signal Propagation Delay

Quick fact

Even in a vacuum, light (the fastest signal) takes about 3.3 nanoseconds to travel just one meter. In copper wires or fiber optics, delay is longer due to the medium's properties.

Why this is interesting

When you press a button and see a response, there's always a tiny wait. That invisible pause is signal propagation delay—the time it takes for the signal to physically travel the distance.