By Joe Wilcox, Betanews

Apple executive briefing at first Apple retail store, May 2001.

Ten years ago -- that's right, 2001 -- Apple made four investments that bore fruit in a 21st-century success story. Everything that came afterwards, even iPad and iPhone, traces back to what I call the "2001 Four."

Apple made these investments during difficult times. The dot-com bust rippled disastrously through the tech industry, the United States was gripped in recession and Apple's stock value had collapsed. Shares opened at $343.72 today about four bucks off the 52-week high. Apple's market capitalization was $317.21 billion at yesterday's close. Going back in time, Apple shares traded for less than $10 a decade ago. As I explained last month, Apple's fortunes have dramatically changed.

The four investments all turn 10 this year, and there surely will be anniversary stories from Mac enthusiast blogs and news sites, perhaps even from more mainstream media. But I expect few, if any, will capture the significance of the 2001 four:

1. In January, Apple unveiled the iTunes music player.

2. In March, Apple launched troubled Mac OS X 10.0 and relaunched as 10.1 in September.

3. In May, the company opened Apple Store, in two locations -- California and Virginia.

4. In October, the first iPod debuted.

Apple's Gang of Four

At the time, iTunes Mac OS X, Apple Store and iPod, seemed like innocuous launches, but they would later be the four pillars raising Apple's brand from obscurity to mass popularity.