Quantities and Unit Conversions--Chemistry 11 By Sally Chen

Quantities
-All measurements in Science come in 2 parts: the number + the unit.  These number and unit combinations are called quantities.

-Basic units: 
Length                                    Metre                                  m
Time                                       Second                                 s
Mass                                     Kilogram                               kg
Amount of Substance              Mole                                     mol
Luminous Intensity                 Candela                                  cd
Temperature                           Kelvin                                    K
Electric Current                      Ampere                                   A

Unit System
SI system:
  --A French system dating back to the early 1800's using prefixes and symbols.
  --metre-second-kilogram
Imperial System:
  --feet-second-pound

SI Prefixes and Conversions Factors

Link:

How to Convert Units of Measurement