Half a century of Hot Wheels. Can you believe it? Oh, metal toy cars existed long before Mattel’s eternal “blue brand” (so named for the color of its packaging), but Mattel’s timing and ideas combined to fire the imagination of generations of kids, building a billion memories in the process.

To understand why they were such a phenomenon, you have to understand what came before. In the ’50s, Tootsietoy made diecast cars in a variety of sizes, including 3-inch scale (roughly 1/64, or S-scale). They were charming but crude: a body featured faint cast-in detail, so-so paint and a pair of barbells (wheel/axle combinations) clamped in to stanchions jutting down from the body. There was no chassis, interior, nor glass on cars of that size in those days.

When England’s Matchbox burst on the scene in the mid-’50s, their small cars offered a new level of detail: interiors, chassis, the occasional trailer hitch, and (in the early 1960s) window glass. Their cars were roughly OO scale (1:76) but grew over time to the familiar 3-inch size. They covered vehicular subject matter from around the world. Across the globe, they were favorites among boys of a certain age (and likely not a few girls, also) for most of the 1960s.

And then along came Hot Wheels. And they pretty much wrote the book on die-cast automobiles.