Re: What does SI stand for?

Hi Melissa,
 
    SI is another way of saying "International System" of units.  The 
abbreviation SI comes from its french name: "Systeme Internationale".  In 1960, 
an international committee established rules to decide on a set of standards 
for the fundamental quantities used in the sciences.  It is a system set up so 
that we all use the same units and avoid confusion.  

    In this system, the standard units used are:  kilograms for mass,  meters 
for distance, and seconds for time measurements.  These are the most commonly 
used units.  There are also SI units for other things like temperature, 
electricity, and luminosity.  So if someone asked you to compute or measure 
something in terms of SI units, you would determine numbers using the above 
units.