It even says so on the package:
What the (insert your favorite word here) are Hydrox, anyway? Well, I'm glad you asked.
Hydrox cookies look like Oreos but somehow predate them, being introduced in 1908. I wonder how that works? They are a bit different than Oreos, being crispier with darker chocolate crackers and less sweetness overall (though they are still plenty sweet)—kind of like the difference between Coke and Pepsi.
How come you've never heard of them? I expect you're just way too young to have experienced the preeminent sandwich cookie. Leaf Brands, the company that made them, was bought in the 1990's. Hydrox was reformulated and the name changed in 1999. They disappeared completely by 2003. But now they're back, with the original name and formula.
Why am I telling you this? I just had to tell somebody! I grew up loving Hydrox (not that I've been around since 1908) and not the competition.
But here's the real question: Are they just as good as I remember? The answer: Is anything, really, as good as we remember? Don't get me wrong—they are still quite tasty and my personal choice over Oreos, but like lots of the memories of one's youth, the reality does not quite bear out.
Hydrox are not in every store, yet, but you know where you can find them:
Hydrox on Amazon