Fiber optics are thin strands of glass that transmit light signals over long distances. They work by having light bounce within the core via total internal reflection. While light can travel great distances through fiber optics with little loss, some degradation does occur due to impurities in the glass. Fiber optics are used in communication systems similar to how naval ships would use signal lights to communicate, and they have advantages over copper wire including being able to transmit more data over equivalent cable lengths while having a smaller diameter.