Prime Day vs. Black Friday: Which sales are better?

The difference between Prime Day and Black Friday — their roots, anyway — probably isn't a mystery to anyone who has dabbled in online shopping before. Most of us know that Black Friday is the big sale frenzy that happens around Thanksgiving as a precursor to the holidays, and that almost every store you can think of participates. Alternatively, the name "Prime Day" suggests that the event is indeed an Amazon-specific event made up by Amazon for members of its Prime…