From Floppy Disks to DVDs: The Wild Evolution of Computer Memory

-Karthik Gurumurthy

It’s amazing how quickly storage technology evolved and how primitive those solutions seem now compared to what we have today.

Remember ten years back we had floppy disks? Those plastic-encased magnetic disks came in two sizes – 3.5 inches and 5.25 inches – and held anywhere from a measly 100,000 bytes to 1.44 megabytes of data. That’s right, MEGABYTES! The drive would spin them at a sluggish 300 rpm, and they didn’t even start spinning until you actually requested data. Compare that to hard disks that were constantly whirring away at 2,400-3,600 rpm (except in laptops, which conserved battery by only spinning when in use).

Hard disks were the workhorses of computer storage, sealed inside the computer with stacked pieces of aluminum coated with iron oxide.. Typical PCs came with hard disks holding 2-6 gigabytes, which seemed enormous back then. A byte was explained as the equivalent of a single character, with 1 megabyte equaling 1 million bytes and 1 gigabyte equaling 1 billion bytes.

For backing up important files, there were solutions like Digital Audio Tape (DAT) cartridges, which looked like audio cassettes but could hold two gigabytes of data. The book emphasized how important it was to routinely back up files in case of hard disk damage – advice that’s still relevant today!

The 1990s saw an explosion of removable storage options. There were removable hard disks like the Quest drive (4.7GB), Zip cartridges (100MB), and Jazz cartridges (1-2GB). Then the optical revolution began with CD-ROMs, which could hold 650MB of data and were read by lasers. Unlike magnetic media, these discs were “read-only,” perfect for distributing software, games, and multimedia.

By 1997, we had both CD-Rs (recordable CDs) and the newly introduced DVD, which resembled CDs but could hold 4.7-17GB of information – a massive leap forward which was a big deal.  We also had Magneto-Optical (MO) cartridges that combined magnetic and optical technologies, storing between 128MB and 2.6GB of data.

Inside the computer itself, we had two critical types of memory:

1. ROM (Read-Only Memory) – permanent storage for the computer’s operating instructions that stayed intact even when powered off
2. RAM (Random-Access Memory) – temporary storage that held programs and data being actively used, but wiped clean when the computer shut down

RAM was particularly important – the more RAM a computer had, the faster it operated and the more complex programs it could run. You could upgrade your RAM by purchasing SIMM (Single In-line Memory Module) chips and plugging them into available slots on the motherboard.

What’s fascinating is how the fundamental concepts haven’t changed much, but the capacities have exploded. Today’s storage solutions measure in Gigabytes rather than megabytes, but the basic division between permanent storage (hard drives, SSDs) and temporary working memory (RAM) remains the same.

Looking back, it’s mind-boggling to think how excited we were about storage devices that held just a fraction of what even the most basic smartphone can handle today!