5. Boot Camp lets Intel Macs boot Windows (2006)

What happened: Once Apple started building Macs powered by Intel-designed processors—more on that momentarily—it didn't take much to get Microsoft's Windows operating system running on Mac hardware. That turned out to be Boot Camp which let Intel-based Mac owners boot directly into Windows XP. Boot Camp is now built into Mac OS X, while third-party developers offer virtualization software that let you run Mac and Windows on the same machine.

Why it matters: The ability to seamlessly run Windows on a Mac removes one more obstacle that might otherwise keep corporate IT departments from letting their employees use Mac hardware. Boot Camp and third-party virtualization offerings make the Mac a more attractive option in settings where the Mac never would have been welcomed at the start of the decade.

4. Apple begins the transition to Intel processors (2005)

What happened: Steve Jobs dropped a bombshell in his 2005 Worldwide Developer Conference keynote when he announced that Apple would drop PowerPC processors in favor of Intel chips. Apple would introduce its first Intel-based machines six months later, in the form of the iMac and the MacBook Pro. By the 2006 WWDC, Apple completed the Intel transition with the release of the first Mac Pro. And the Mac OS X update released this year only runs on Intel-based hardware.

Why it matters: The PowerPC processor had gone about as far as it could go. Switching to Intel chips opened new possibilities for Apple, and the company has delivered with a steady stream of updates that have the Mac in exciting new directions. And, as noted above, Intel-based hardware can run Windows, making the Mac a more attractive option for businesses.

3. Apple releases the original iPhone (2007)

What happened: It was easily the most dramatic moment of the decade: At the end of his January 2007 Macworld Expo keynote, Steve Jobs reached into his pocket and pulled out the first iPhone. It's safe to say that Apple—and the mobile phone market as a whole—hasn't been the same since. In the two-plus years and two iPhone updates since that moment, Apple has sold more than 33 million phones with no signs of slowing down any time soon.

Why it matters: Like another Apple portable device we'll get to in a moment, the iPhone was a game-changer—both for smartphones and for Apple itself. Any smartphone to come down the pike these days invites inevitable comparisons to the iPhone. Meanwhile, Apple has found itself another source of revenue to go along with its Mac and music businesses.

2. Mac OS X 10.1 comes out (2001)

What happened: Apple actually overhauled its Mac operating system in March 2001, replacing the classic Mac OS with OS X. OS X 10.1—“Puma” to its close friends—would follow later that year, and while the Aqua interface and Cocoa and Carbon APIs that marked the new OS were already in place, this version introduced the improvements that made OS accessible to most users.

Why it matters: For Apple's core Mac business, nothing matched the impact of the switch to OS X. It paved the way to wider use of the Mac platform and set a standard that forced other OS makers—we're looking in your direction, Redmond—to step up their game. Honestly, I could have picked any of the OS X updates that Apple ushered in throughout the decade, but in this scribe's opinion, 10.1 was the version that signaled Apple's new OS was ready for prime time.

1. Apple releases the first iPod (2001)

What happened: At an October 2001 press event at its Cupertino headquarters, Apple unveiled a music player with enough capacity to hold 1,000 songs. The portable music player soon became ubiquitous—adding Windows compatibility in 2002 certainly helped in that regard. And even with iPod sales growth slowing down, Apple still routinely sells 10 million music devices a quarter—unless it's during the holidays, when that sales figure doubles.

Why it matters: Mac purists may shudder at the thought, but the iPod indicated that Apple was more than just a computer company. The device established the company as a leading player in the digital decade, when we began to rely less on physical media for our entertainment and more on digital files. As the iMac helped revive Apple's fortunes in the previous decade, the iPod padded Apple's profits, setting the tone for a successful—and lucrative—decade to come.

But that's just one man's list. I'm sure there are plenty of other milestones from the last 10 years that I've overlooked.