The Windows operating system has made evolutionary leaps and bounds since Windows 1.0 launched in 1985.

Last week, Microsoft set its sights on reaching new heights with the launch of its latest version of the iconic OS, Windows 8. And so far, the company is off to a great start. CEO Steve Ballmer announced that the company has already sold 4 million Windows 8 upgrades at Microsoft's annual Build conference.

The company's first few operating systems (Windows 1.0 - Windows 3.11) were once the epitome of innovation. They had everything consumers didn't know they needed: an analog clock, Paintbrush to create high-tech graphics, and innovative games, such as Reversi and Minesweeper. Yes, Minesweeper was a breakthrough in its heyday.

But Microsoft didn't find its true sweet spot until the trailblazing Windows 95. With this release, Windows transitioned from a 16-bit architecture to a 32-bit architecture, and users were introduced to Outlook Express and Internet Explorer, two programs still in use today.

Before you join the more than 4 million users who have upgraded to Windows 8 since last week's launch, view the infographic below to see where it all began.