1. The fiber strand consists of three layers. The core is in the center, is made of the highest quality optical glass, and carries the light signal. The cladding surrounds the core, is made of a different grade of optical glass, and keeps the light signal within the core when the fiber is bent. The buffer coating surrounds the cladding, is made of plastic, and provides strength and flexibility to the fiber.

2. The speed of light in optical fibers is slower than the speed of light in a vacuum. The speed of light in optical fibers is called the "Index of Refraction", and is a numeric value between 1.400 and 1.5999, with lower numbers indicating a faster speed of light.

3. The difference in the compositions of the glass used for the core and the cladding cause light rays to stay within the core. This property is called "Total Internal Reflection".

4. The diameters of the core, cladding, and buffer coating are standardized within the fiber optic industry.

5. When a fiber strand is "stripped" in preparation for splicing or connectors, the buffer coating and any outside jacketing material is removed.

6. The core and cladding are always together. Stripping DOES NOT REMOVE THE CLADDING.

7. Light signals in multimode fiber use many paths to travel from the transmitter to the receiver. Pulse spreading limits the useful distance of multimode fiber to less than five miles.

8. Singlemode fiber has a much smaller core than multimode. Light signals in singlemode will travel one path from transmitter to receiver.

9. Singlemode fiber is used for long distance, high bandwidth applications. High cost laser transmitters are used.

10. Multimode fiber is used for shorter distances, and is attractive because inexpensive LED transmitters are employed.

11. A fiber strand with a connector on each end is called a fiber "link".

12. Fiber cannot be branch circuited or "T tapped". Signals must originate at point "A", and be received at point "B".

13. The wavelengths used in fiber optics are standardized for transmitters, receivers and test equipment.

14. 850 and 1300nm are used in multimode, while 1310 and 1550nm are used with singlemode fiber.

15. LIGHT SIGNALS IN FIBER OPTICS ARE INVISIBLE TO THE HUMAN EYE. VIEWING A FIBER END CONNECTED TO AN INVISIBLE LASER TRANSMITTER CAN DAMAGE YOUR EYESIGHT.