Here's what is open on Black Friday, from the post office to the stock market

Black Friday is a major event for retailers opening their doors for shoppers looking for holiday bargains, but the day after Thanksgiving is business as usual for much of the rest of the U.S. 

Many major retailers shut their doors on Thanksgiving, including Walmart, Costco, Kohls and Target. 

But all of those chains are open on Black Friday, although some may have extended hours to cater to shoppers.