The first few days after Labor Day are typically pretty busy for companies that borrow money by issuing bonds.

In order to raise cash ahead of the winter holidays, companies tend to issue a wave of long-term debt — bonds with terms in the years or even decades.

But another type of corporate borrowing has been surging all year. A type of short-term debt that’s paid off much faster than your typical corporate bond and known as commercial paper.

The commercial paper market is kind of like that 2 p.m. snack before dinner. It’s probably not loaded with fiber or protein, but it will hold you over for a little while.

“It kind of provides a low-cost, instantaneous almost, cash infusion,” said John Bai, a finance professor at Northeastern University.

He said commercial paper typically matures in months. Or even days.

Companies don’t use it to finance expansions or acquisitions or other long-term plans. Instead, they spend it on the basics.

“Paying the employees,” Bai said. “Paying your suppliers on time.”

Up until recently, borrowing money on the commercial paper market has not been that popular.

Winnie Cisar, head of strategy at CreditSights, said that after the financial crisis of 2008, interest rates were near-zero for years.

“If a company can lock in a 10-year bond for a relatively low yield, a lot of companies like that certainty,” Cisar said.

But this year, interest rates on long-term bonds have shot up, thanks to concerns about the economy, government debt, and inflation.

Cisar said many companies don’t want to lock themselves into decades of bond payments at today’s high rates.

“Going to the commercial paper market, where you know that you’re not going to be locked in for a particularly long period of time, makes a lot of sense,” Cisar said.

There are risks involved with short-term debt. Lawrence Gillum at LPL Financial said companies have to keep re-borrowing whenever it matures.

And a lot can happen before commercial paper comes up for renewal.

“The macroeconomic environment could change,” Gillum said. “Your corporate profile can change.”

But right now, Gillum said companies think those risks are worth it. Especially if interest rates come down soon.

Bai said many companies are thinking that long-term investments are riskier.

“This surge in commercial paper is probably reflecting the short-term orientation and the nature of company thinking these days, at least for this year,” Bai said.

Because when the economy is uncertain, short-term debt can help companies wait it out.