 The two-day summer sales extravaganza runs through Wednesday. Since it began in 2015, Amazon's Prime Day has become one of the most significant shopping events in the world. This year, shoppers are expected to spend about $14 billion, according to estimates from Adobe Analytics. That's a lot of money, reporter Hilary Barsky. And not to be outdone, Walmart, Target and Kohl's and a few other big box stores are also offering discounts today, hoping you'll do a little shopping with them.