When Steve Jobs first pulled the MacBook Air out of a manila envelope in 2008, it wasn't just a crazy-thin laptop—it was a downright crazy idea. For nearly $2,000, you got a notebook with no DVD drive, a minuscule amount of storage and ports, and an underpowered processor.

That crazy idea turned out to be the future of laptops. Nearly six years later, the laptop—from its tapered aluminum exterior to its compact internal organs—has been copied by nearly every Windows PC maker.

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