Price elasticity of demand is often shortened to PED
A PED can be different variations of elastic, inelastic or unit elastic.
What PED is is the responsiveness of demand to a change in price.
The three main types of elasticity are:Elastic: means that a change in price will result in a relatively large change in demand. (usually things like furniture or cars or things with substitutes ie. pepsi/coke)Inelastic: means that a change in price will not result in much change at all. (demerit goods like cigarettes, medication)Unit elastic: means that a change in price will have a proportional change in demand.
To work out your PED you'll need an equation = % changed in QD/ % changed in P:If PED> 1 then the good is price elasticIf PED<1 then good is price inelasticIf PED = 1 then good is unit elasticIf PED= 0 then good is perfectly inelasticIf PED= infinity then goof is perfectly elastic
You can show the elasticises pretty well on a graph.