(Washington, DC) -- There's a lot of buzz about a looming government shutdown but, if that happens, it will not spread to the entire federal government.

Many government employees involved in defense, homeland security and public safety will remain on the job, including airport screeners, air traffic controllers, federal prison guards and border inspectors. The U.S. mail will still be delivered. Social Security and Medicare checks will continue to be processed and mailed, along with veterans benefits.

On the flip side, several hundred thousand federal government employees will likely be furloughed in dozens of federal agencies and departments.

National parks, monuments and museums will start closing and the processing of passport applications will come to a halt. A shutdown is likely at midnight tonight unless the Senate, House and White House agree on a funding extension. Midnight signifies the end of the current fiscal year.