A government shutdown is when Congress can’t agree on funding bills to keep agencies and programs running. This pause in paychecks hits workers and their families hard, and it costs the economy, too, says an analysis from the Congressional Budget Office. It adds that longer shutdowns reduce economic output and cost taxpayers money they never recoup.

Some services continue during a shutdown, including Social Security and Medicare cheques, in-hospital medical care, air traffic control and national parks. Workers deemed essential, such as border protection and law enforcement officers, remain on the job but are not paid.

But for many other federal employees, work stops. That means some of the country’s most important scientific research is on hold. For example, this shutdown affects scientists at the Centers for Disease Control and Prevention and at the National Institutes of Health, and a number of ongoing clinical trials. Other federal employees, including those whose duties are not considered essential, are sent home without pay and are required to receive back-pay once the government reopens. But they may miss mortgage and car payments, or struggle to meet other basic financial obligations.

NPR’s entire network of state newsrooms is investigating the ways in which this shutdown is impacting people across the country. You can listen to some of their stories below, and see the full list here. And for more information on the history of shutdowns and their effects, click here. Sen. Jeff Merkley, D-Oregon, is speaking on the Senate floor in protest of this shutdown.