I'm not quite sure why Amazon chose 7.16 as Prime Day, since it isn't a Prime number. But regardless, as a prime member I'm happy whatever day it is.
I don't think that 5 years ago anyone could have convinced me how much I'd come to rely on Prime in my day to day life. It's become a convenience and a habit and a life saver. I assume without children, I'd still be an avid user, but with my inability to get to a store alone, the need to bargain shop, and the apparent urgency of wants and needs, I can't imagine parenting without it. And now with the extra deals at Whole Foods as Prime members, it's getting even better.
If you are one of the few people who don't have Prime, use the link to get a free month. And if you don't yet have Prime Pantry, I'd recommend at least a trial. It was a great time saver for us, and you can always cancel if you end up not liking it.
But, Prime Day. Lots of good deals, if you are in the market for it. I put together a list of my favorite Prime-shipping lettering supplies. Stock up!