A multi Mode fiber has a Core diameter larger than the Wavelength of Light transmitted. Multi mode Fiber allows for many modes, or rays of light, to travel down the core simultaneously.
Multi mode fibers are optical fibers that are designed to carry multiple light rays at the SAME time, meaning that they can carry more Data than a Single Mode fiber, but cannot transmit nearly as FAR as single mode fiber. Multimode fiber optic Cables are much more effective for communicating over shorter distances than single mode fibers.
Multi mode fiber optic cables have core diameters of 50 µm or 62.5 µm.