As President Donald Trump and congressional Democrats clash ahead of a partial government shutdown that could start Oct. 1, thousands of federal workers are faced with potential furloughs.

Barring a late breakthrough to avert a shutdown, government functions deemed non-essential, like national parks, will close or cut staffing, while essential government services, such as the military and law enforcement, will keep working.

While government shutdowns have occurred in the past, pressure could be higher for federal workers this time around because the White House has threatened layoffs, rather than temporary furloughs.

Here's what to know about what furloughs are and how they differs from layoffs.

What does it mean to be furloughed?

A furlough is the "placing of an employee in a temporary nonduty, non-pay status because of lack of work or funds, or other non-disciplinary reasons," according to the Office of Personnel Management (OPM). When an agency does not have enough funds, such as in the case of a government shutdown, a “shutdown” furlough occurs and those employees not categorized as "excepted," or essential, pause their work.

Job-matching and hiring site Indeed describes a furlough as mandatory time off, typically implemented by companies as a cost-saving measure. Furloughs are temporary and the length of a furlough leave can vary, "from a reduction of hours per week to several months without work," according to Indeed's definition.

What is the difference between furloughs and layoffs?

While a furlough is mandatory time off, employees who are laid off are permanently let go from their jobs and do not have the option to return.

Additionally, in a furlough, employees continue to receive benefits, according to OPM.

Are furloughed employees paid?

Ahead of the potential Oct. 1 shutdown, OPM said furloughed workers would receive "appropriate retroactive pay for periods of furlough" after a potential shutdown ends.

Previously, federal workers were temporarily furloughed until lawmakers reached deals to resume the government with Congress later voting to ensure the employees are paid during their time away. During the most recent 35-day shutdown, back in 2018, about 380,000 workers were furloughed while another 420,000 were on the job without pay (they were guaranteed back pay, though.)

When could a government shutdown happen?

The current funding for the government expires after 11:59 p.m. on Sept. 30, with Oct. 1 being the potential start of a partial government shutdown.

Saman Shafiq is a trending news reporter for USA TODAY. Reach her at sshafiq@gannett.com and follow her on X and Instagram @saman_shafiq7.

This article originally appeared on USA TODAY: What does it mean to be furloughed? What to know as government shutdown looms

Reporting by Saman Shafiq, USA TODAY / USA TODAY

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