An optical fibre is a cable made up of super-thin filaments of extruded glass (silica) or other transparent materials that is able to carry beams of light. This super-thin glass filament functions as a wave-guide, or “light pipe“. Optical fibres are largely used for fibre-optic communications to permit transmission over longer distances and at higher bandwidths(data rates), which wire cables are not cable of. A fibre-optic cable is light-based and so data can be sent through it at the speed of light. Fibre-optics are based entirely on beams of light so they are less susceptible to noise and interference than other data-transfer mediums such as copper wires or telephone lines. Light is kept in the core by total internal reflection and this lets the fibre to act as a wave-guide. Joining lengths of optical fibre is more complex than joining a electrical wire or cable and so their ends must be carefully cleaved.