Perfect substitutes

Normal goods

Perfect compliments  

Close substitutes  

Total effect of price change on consumption of a good is a combination of income effect and substitution effect

For inferior goods, income effect is always larger than substitution effect, in absolute terms.  

For corner solution \(\rm \operatorname{MRS}_{x y} \neq \frac{\mathrm{P}_x}{\mathrm{P}_y}\)

For a normal good both the income and substitution effect hold