Pulse propagation refers to the way a pulse of energy, such as a light wave or sound wave, travels through a medium. This process can occur in various materials, including air, water, and optical fibers. The speed and shape of the pulse can change depending on the properties of the medium, such as its density and elasticity. In the context of optics, pulse propagation is crucial for technologies like fiber optic communication, where light pulses carry information over long distances. Understanding how pulses behave helps engineers design better systems for transmitting data efficiently and accurately.