Fiber optic plugs are cables made to transmit signals of light as opposed to electricity. These cables allow for quick transmissions through long distances and are made up of glass, plastic, metal and sometimes other materials.
Fiber optic cables are made primarily of glass fibers. These fibers must be properly aligned so that light can evenly pass through and create a solid connection between the connected sources.
The other materials found in fiber optic cables are steel, ceramic or plastic. These materials make up the ferrule, connector body and coupling mechanism. The ferrules hold the glass fibers in place, the connector body strengthens the ferrule and the coupling mechanism connects the cable to its specified device.