Punched cards, baby!
Check out these IBM RAMAC platters sharing a single, very overworked
read/write head moving up and down a tower service assembly:
The Cray model 1A super computer, serial number 6, from 1976. (For an idea of scale, it's over seven feet tall.)
A hard drive assembly from Digital Equipment Corporation (DEC), circa 1970. (For an idea of scale, it's over a foot across.)
Here's a whole computer system from fifty years ago: The IBM model 305 RAMAC system, circa 1957. Note the truck-sized hard drive cabinet using the same single-head tower stack from three pics up.
And for an image of a modern computer to compare...well, look in front of you.* The one you're using right now has VASTLY more computing power than did the Apollo spacecraft that took mankind to the moon in 1969. In fact, only ten modern homes like yours likely contain more total computing power than the entire United States Air Force had in the same year. It's difficult to realize just how FAST our computing power grows over time until you live long enough to really experience a good chuck of it. For me, it started as I tinkered around with building rack systems in the late '70s. A gigabyte? That was the realm of, well, the US Air Force. It was around the same time a guy named William was having brighter ideas than me in this industry and sowing the seeds for the biggest financial empire the world's ever known. Damn it.
* - I doubt you're surfing the forum on an Altair, but if you are then please forgive my assumption.