What is inflation? Why prices rise, what the rate means, and who it hurts the most.

Over the few years, inflation has been cooling. But from the gas pump to the grocery store, the overall price of living still feels stubbornly high for many Americans. The Federal Reserve has tried to strike a fragile balance: bring inflation down by raising interest rates, without pushing the economy to the brink.

While it is easy to see and measure those price changes, it is something else to actually understand them. Inflation can impact many things besides costs, such as employment and wages.

So, what is inflation, and what causes it?

What is inflation?

Inflation is a "generalized rise in prices," said Josh Bivens, the director of research at the Economic Policy Institute, a left-leaning think tank based in Washington D.C. For example, goods like gas, rent or food can be impacted by inflation.

"Inflation, though, really is meant to only refer to all goods and services, together, rising in price by some common amount," he explained.

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What causes inflation?

Inflation can be caused by several factors. The most common is "a macroeconomic excess of spending over the economy's relative ability to produce goods and services," Bivens said.

In this instance, more people are spending money on goods or services that are not readily available to meet those demands, so producers begin to raise prices.

"If everyone in the economy, tomorrow, decided they weren't going to save any money from their paychecks, and they're just going to spend every last dollar out of the blue, they would all run to the stores and try to buy things," Bivens said. "But, producers haven't produced enough to accommodate that big surge of across-the-board spending. So, you would see prices bid up."

Another cause of inflation is a lack of producers. If there are not enough workers to produce the demanded good or service, this would lead to an increase in prices as well, Bivens said.

"Labor is the primary component of cost of producing anything," he explained.

There is also a level of "built-in inflation" within economies, where central banks try to get inflation to hover roughly at a certain level.

In the U.S., the Federal Reserve's target inflation is 2%. This means businesses can increase prices by 2% each year, and it shouldn't impose a cost burden on consumers. Workers can also ask for a 2% wage raise based on these increases, so they can still afford goods and services.

"That 2% is kind of the built-in inflation; what everyone expects to happen," Bivens said.