sheck33 once bubbled...
The Kelvin is a more fundamental temperature scale as it is more solidly linked to thermodynamics, absolute zero being the temperature at which molecules have the lowest possible energy. as a side note many physical laws and formulas can be expressed more simply when an absolute temperature scale is used. The references chosen for the Centigrade & Fahrenheit scales are on the other hand completely arbitrary, the boiling point of water depends on pressure & purity of the water for example. On the Celsius scale used today, which is defined differently, the boiling point of water is just a little under 100 degrees centigrade. Temperature measurement & definition of scales is not a trivial thing but very interesting
some reading material :
http://www.unidata.ucar.edu/staff/blynds/tmp.html
True Kelvin is a more technical scale but Celsius follows the same units as kelvin but just starts at a more friendly level ie the frezzing point of water. It would be pretty ludicrous to use Kelvin in everyday life, wow the water was 300 Degrees K today. Pretty cold it was 269 degrees outside today.
Ok imperialists how many feet in a chain? and how many pints in a firkin