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The demand for a good is elastic with respect to price if its price elasticity of demand is greater than 1.
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The demand for a good is inelastic with respect to price if its price elasticity of demand is less than 1 unit.
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The demand for a good is unit elastic with respect to price if its price elasticity of demand equals 1.
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Perfectly elastic demand: demand is perfectly elastic with respect to price if price if elasticity of demand is infinite.
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Perfectly inelastic demand: demand is perfectly inelastic with respect to price if price elasticity of demand is zero.
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Cross-price elasticity of demand: percentage by which the quantity demanded of the first good changes in response to a 1 percent change in the price of the second.
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Income elasticity of demand: percentage by which quantity demanded changes in response to a 1 percent change in income.
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Price elasticity of supply: percentage change in quantity supplied that occurs in response to a 1 percent change in price.
Perfectly inelastic supply: supply is perfectly inelastic with respect to price if elasticity is zero.
Perfectly elastic supply: supply is perfectly elastic with respect to price if elasticity of supply is infinite.
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