Andrew, a college student, loves drinking coffee late at night to study for exams. Having no income, he is used to buying cheap, bad-tasting coffee, such as Beanlightened, that he needs to grind and brew himself. The coffee tastes putrid but, with enough cream and sugar, Andrew is able to tolerate it. Occasionally, he does go out to Starbucks when he has spare money. After graduation, Andrew gets a job working at a database firm as a programmer. His income is now a healthy $75,000 a year, and he decides he has had enough bad-tasting coffee. He ends up buying coffee daily from Starbucks, even though it costs significantly more than Beanlightened.

Starbucks Coffee is a 'normal good', while Beanlightened coffee is an 'inferior good'.

Andrew's demand for Starbucks coffee changed as a result of an increase in his 'income'

Explanation:

A normal good is a good that sees it's demand rise as income or wages rise. Essentially if you're making more money, you buy more of such goods. Andrew is now making more money so he buys more of Starbucks coffee.

An inferior good on the other hand is one that sees it's demand drop as wages or income rises. You usually buy less of it the more money you make. Take no brand cornflakes for instance, as one makes more money they tend to buy less of it and more of branded cornflakes. Beanlightened coffee is therefore an inferior good.

Income is compensation you get for providing a service. In this instance Andrew receives $75000 a year for being a programmer.