A single mode fiber-optic cable is constructed to allow only one mode of light to travel through its diametral core. The core's small size reduces light reflections, increasing the distance that signals can travel and preserving signal quality. A multimode fiber-optic cable is constructed to allow multiple modes of light to travel through its diametral core. The core's large size increases light reflections, allowing more data to travel across at the cost of reduced signal quality. Because signal quality drops as distance increases, multimode fiber is generally used for short-distance communications across local area networks (LANs).