Fiber-optic (FO) cables transmit data in the form of light across long routes. To achieve this, the electrical signals at the transmitter are converted into optical signals and sent to the receiver through plastic or glass fibers. The light is a form of carrier wave that is modulated to carry information. It enables data rates of up to 40 Gbps over routes that are many kilometers long, does not have a negative effect on adjacent cables, and at the same time is resistant to. The diagram above shows how electronic input signals get transformed into light pulses, travel through a fiber optic cable, and are converted back into electrical signals when they reach the receiver.