Nintendo DS

Nintendo pitched the DS as a "third pillar," an experiment that would sit beside the Game Boy line and the home consoles without necessarily replacing anything. Behind that modest framing was a radical machine: two screens, the lower one a resistive touchscreen operated by stylus or thumb, plus a microphone, wireless connectivity, and a slot that kept the vast Game Boy Advance library playable. In an era when the industry chased horsepower, Nintendo chased new ways to interact.

The clamshell hardware was deliberately approachable rather than powerful, and its second screen unlocked interfaces no other platform could offer, maps, inventories, drawing surfaces, and touch controls that felt intuitive to people who had never held a controller. That accessibility was the whole strategy. Brain Age, Nintendogs, and the Professor Layton and Cooking Mama games pulled in commuters, retirees, and non-gamers by the tens of millions, while New Super Mario Bros., Mario Kart DS, Pokemon Diamond and Pearl, Animal Crossing: Wild World, and The World Ends With You kept the traditional faithful enthralled.

It was a titanic success. Across its many revisions, the slim Lite, the camera-equipped DSi, and the jumbo DSi XL, the DS family sold roughly 154 million units, making it the best-selling handheld ever built and one of the best-selling gaming devices of any kind. It comfortably outsold Sony's more powerful PSP and helped Nintendo dominate a generation.

The DS's importance runs deeper than sales. It demonstrated, alongside its cousin the Wii, that intuitive, novel controls could expand gaming's audience far beyond young men, briefly turning "casual" players into the industry's center of gravity. Its dual-screen, touch-first design language flowed directly into the 3DS and shaped expectations for touch interaction just as smartphones began their own conquest. For a decade the DS was ubiquitous, tucked into pockets and handbags across the world, a quiet revolution disguised as a toy.