(WETM) – Tax season may be one of the most dreaded times of the year, especially if you have to fill out your return yourself. Plugging in all those numbers can be confusing, and if you have a business, it’s even more complicated.

At the end of the day, you may not even bother thinking about what it is exactly you’re doing or why, but just send off the form to the IRS and wait to hear back.

But what is a tax refund and why do we get them?

When you get a paycheck from your company, a certain amount of money is withheld for state and federal taxes. In the simplest of scenarios, the W-2 form you receive during tax season lays out how much money was taken out of your paycheck for programs like Social Security, Medicare, and income taxes.

So then tax season rolls around and you need to send off the numbers to the federal and state governments. This is to determine how much money in taxes you still owe, or how much the government now owes you, US News & World Report explains.

Let’s be honest. When you file your taxes early each year, it’s nice to get a check or deposit for some money. As Investopedia says, when you get money back from the state and federal governments, it’s basically a loan that you issued throughout the year and they’re paying back.

But if you already paid taxes in each paycheck, why are you getting money back?

Simple. Sometimes people overpay in taxes. This could be because your employer withholds more than necessary from your paychecks; or maybe there was a mistake when a worker filled out the W-4 withholding form; or, tax credits you qualify for outweigh the amount of taxes you pay. Some people may even intentionally pay more taxes than necessary so they get a bigger refund.

Of course, the opposite is also true. Not everyone is going to get money back from the government each year.

If your employer didn’t withhold enough from your paychecks, and you ended up underpaying, then come tax season, you’ll be sending money to the government. Not the other way around.