A flexible and transparent fiber made by pulling strings of molten glass or plastic with a diameter slightly thicker than that of a human hair is called optical fiber or optical fibre depending on the English being used US or UK. Since inception optical fibers have been mostly used and designed as a medium to transmit light between the two ends of the fiber and this is the sole reason why they find wide usage in fiber-optic communications. Here they are used to transmit data signals over longer distances and at higher bandwidths compared to the conventional wire cables. Fibers have evolved as an alternative to metal wires because signals transmitted in them suffer less loss.
The most important advantage of using optical fibers is that they are immune to electromagnetic interference which is a huge problem with metal wires; all such important characteristics are well taught using our optical fiber training kits fibre optics trainer boards. An optical fiber is basically a solid core which is surrounded by a transparent cladding materiel with a lower refractive index than the core. The light travels in the core by using total internal reflection which makes the fiber behave like a wave guide.