A potential government shutdown won't affect everyone the same way. There are essential workers, whose jobs must continue, and non-essential jobs that would pause for the duration. But the American public would see the effects of both.

There are about 2.3 million federal workers in the U.S. Those who are deemed essential would continue their work during a shutdown, albeit without pay. Non-essential workers, such as those in certain research fields or who staff national parks, would be furloughed until a new funding deal is reached.

U.S. Postal Service operations, for example, would continue during a shutdown. Most of TSA's workforce is also considered essential, so security screenings at airports would also continue during the busy holiday travel season.

National Parks would remain open, but without staff to look after maintenance. In past shutdowns, the National Park Service warned trash was likely to pile up while staff were furloughed.

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Federal employees who are furloughed would feel the most direct impacts of a shutdown.

In 2018, when the government shut down, many local workers had to lean on Washington, D.C. food banks when their paychecks stopped.

Furloughed workers receive back pay when furloughs end, but the slowdown in the government's far-reaching services can still add up to billions of dollars in costs.

A shutdown may delay everything from DOJ prosecutions to small business contracts and IRS processing for new mortgage applications.

A 1996 Congressional report estimated that it cost $1.4 billion to shut the government down for 27 days. Adjusted for inflation that would be more than $2.8 billion today.