What are the advantages of optical fiber over twisted-pair and coaxial cable?

The reason for twisting is to reduce (but not eliminate) cross talk between the wires. This is caused by induction. Fiber optics don't have that problem and are much faster. Although the light pulses have to be boosted intermittently, the signal does not degrade over distance like electric pulses do.

Much much faster.
+5

One advantage not yet mentioned - optical fiber is non-conductive. Fiber is immune to high-voltage spikes and can be used to connect equipment where complete electrical isolation is required to prevent ground loops, lightning transmission, etc.

Also, for equivalent bandwidth capability, an optical cable generally has (or can have, depending on how it is constructed) a much smaller bend radius than a copper cable. This can make a big differences where hundreds or thousands of connections need to go into one switch or patch panel.

Finally, optical cables are generally lighter than copper ones.

Speed Speed Speed ... then you run into distance .. Fiber has the longer distance...

Advantages: More bandwidth, no electromagnetic interference, distances up to 70km.

Disadvantages: Cost, can not be toned(make sure you document it properly).

Fiber optics use light to communicate information, so you are certainly going to have much quicker communications with a fiber optic connection.

Yeah speed is the obvious answer. Though 10b2 wasn't very reliable and required additional components which added to points of failure.

Speed
Distance before lose of signal
Not affected by electromagnetic interference

optical fiber have very high speed and the noise ratio is less