Twenty Years Ago Today, Apple Shipped Mac OS X 

It’s hard to believe that Mac OS X macOS is two decades old, but it’s true. On March 24, 2001, Apple released the first non-beta version of Mac OS X 10.0:

Mac OS X 10.0

The release followed years of development that took NeXT’s technology and molded it into an operating system for the Mac. That process took longer than Apple had predicted, and included a false start known as Rhapsody. That’s really a story for a different time, but in short, that operating system strategy left classic Mac OS developers without a way forward for their applications that didn’t require rewriting them, and the community soundly rejected the entire thing.

After a regroup, OS X began to take shape, with a new technology named Carbon that would allow apps written for the Mac to run natively on the new operating system with some tweaks. I truly believe Carbon is the real hero of the OS X transition, as without it, I don’t think it would have been successful.1

However, Aqua grabbed all the attention. First introduced in Developer Preview 3, this new user interface was shockingly different from Platinum in Mac OS. Full of pinstripes and bright blue elements, Aqua was designed to be as friendly and fun as the colorful iMac G3s with which many users would first experience it.

All of that eye candy came at a cost, though. Performance in the early versions of Mac OS X was notoriously bad as the hardware caught up. By the time most users were ready to switch from Mac OS 8 or 9, OS X was in pretty decent shape.

If you want to learn more about Mac OS X, I’ve rounded up some links for you:


  1. Both Rhapsody and Mac OS X included an environment for running Mac OS apps directly, but these “Classic” programs wouldn’t get any of the benefits promised by the new operating system, including preemptive multitasking, protected memory or an update user interface.