This is Planet Money from NPR.

Hello and welcome to Planet Money Summer School.

The class, the puts the opportunity in opportunity cost.

I'm Stacey Vanick Smith here with an opportunity for macroeconomic learning.

By now we know the origins of macroeconomics, the juggernaut that is gross domestic product,

the ups and downs of the business cycle, all about inflation and money.

Today though, is a really special day because today we are talking about the part of the economy

that is probably the closest to most of our hearts, the job market.

There is a supply and a demand for workers and jobs that really sits at the center of

our whole economy.

This equilibrium is so crucial to the health of our economy and to all of our lives and

when this equilibrium gets thrown off balance for some reason.

It just has an enormous impact on all of us.

When there are for instance, too many workers and not enough jobs, you can get really

devastating unemployment, poverty, desperation, the whole economy can start to unravel like

we saw happened during the Great Depression.

Also when there are too many jobs and not enough workers to fill those jobs, you can see

companies struggling to fill positions.

It can hold back economic growth, push up prices, cause the economy to grind to a halt.

Here to tackle this really monumental economic topic with us is Julia Pollock.

Julia, you are the chief economist with Zipper Cruder, but you've had a lot of other jobs

as well, right?

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