Steve Wozniak

This was classic Wozniak.

While competitors built controllers with dozens of expensive components, Wozniak's design was elegant, it was simple, and it was dramatically cheaper.

But here's the really clever part, the part that showed why Wozniak is in a class by himself when it comes to engineering.

He realized he could offload the controller's functions to the Apple II's main processor.

Other drives use dedicated hardware chips, but Wozniak had the CPU do these tasks and software instead.

He knew it was unconventional.

Most engineers would tell you to use hardware for hardware tasks and keep the CPU free.

But Wozniak realized the CPU wasn't doing anything else at that time.

So why not put it to work?

Why pay for expensive controller chips when you have an idle processor sitting right there?

The result was a disk drive that was incredibly efficient and cost effective.

It made floppy storage affordable for personal computers for the first time ever, and it depended entirely on the expansion slots Wozniak had fought so hard to include.

The Disk 2 that Woz designed in two weeks changed everything, but not in the way anyone expected.

Because in Boston, Bob Frankston and Dan Bricklin had been working on something called VisiCalc, short for Visible Calculator, the world's first electronic spreadsheet, Excel's ancient ancestor.

It was crude, revolutionary, and it was about to change everything.

Before VisiCalc, if you wanted to run financial projections, you had a ledger book and a calculator, and you'd spend hours, maybe days, recalculating everything by hand every time you changed one assumption.

When your sales manager called with new numbers, you'd have to start all over again.

VisiCalc changed everything.

It was Excel before Excel.

You could change one cell and watch all the numbers ripple through instantly.