美国有线新闻 CNN 感恩节购物季开启 黑色星期五由来大起底（在线收听）

AZUZ: If NASA were to track American shopping habits through the seasons, it'd be expecting the whole country to light up in the days ahead.

The traditional holiday shopping season used to start with Black Friday, the day after Thanksgiving, and continue up to Christmas. It's when retail companies launch sales and shoppers go on the hunt for gifts, lines wrapping around stores, people racing down the aisles, trying to get the best deals. This was the norm and still is in some places, but with department stores and online retailers constantly changing the dates of these sales, in many cases, holding them earlier than Thanksgiving, shopping season is now a dynamic event, with no fixed dates.

Safe to say though that by Black Friday, which is this Friday, it's in full swing.

REPORTER: Black Friday sounds kind of scary, and it was. Black Friday first referred to the collapse of the U.S. gold market in 1869. A century later, Philadelphia police used Black Friday to describe chaos and congestion. Downtown streets were clogged with hoards of shoppers headed to the big department stores.

Retailers hated the term but then tried to reinvent it. It was the day their profits went from red to black — so they said.

Black Friday really started catching on in the '80s and '90s pushed by the growth of big box stores.

Today, it's all about bargains and Black Friday's dark roots are for the history books.