Many people remember 2001 as a watershed event for Apple because of the release of the iPod. What many people forget is that before Steve and Co. changed the game in October of that year with what would become the best-selling music device, it released a product that would prove to be just as important to the company: Mac OS X

The tenth iteration of the Mac OS, the new operating system was a monumental undertaking for the company. It was years in the making. It was the first Mac OS that was not backwards compatible with older versions. And it reversed Apple's fortunes in the PC world. Based on the NeXTSTEP OS, from Jobs' former company NeXT, it introduced a number of new and novel features. Many of which would go on to completely change the game. 

To celebrate its 10 anniversary, we decided to take a look at 10 of the features introduced in Mac OS X that we felt were the most innovative. Here's to 10 more years.