1. Price Effect
   1. Change in quantity demanded of a good after a price change in that good
   2. made up of
      1. Substitution Effect
      2. Income Effect
2. Income Effect
   1. Change in quantity demanded
      1. change in real income following price change
   2. can be positive
      1. normal goods
      2. real income and quantity move in same direction
   3. can be negitive
      1. inferior goods
      2. real income and quantity demanded move in different directions
3. Substitution effect
   1. Def
      1. Change in quantity demanded of good due to change in
         1. relitive price
         2. compared with all other goods
         3. following price change
   2. always positive
      1. more of now relativly cheaper
      2. less of now relatively more expensige