In 2004, Lenovo--then known primarily as the largest PC vendor in China--acquired the IBM personal computing division that had once been synonymous with the PC. The industry landscape has shifted dramatically in the 12 years since. Among IBM's contemporary competitors, Gateway and Compaq were gobbled up, the latter by an HP that has split itself in two following the privatization of Dell. And Microsoft continues to push further into the shrinking PC space with its Surface devices.

But one thing hasn't much changed in that span of time--the solid reputation and sturdy black and red-accented frame of the ThinkPad brand. While many doubted whether Lenovo could pull off becoming a leading global PC vendor without the long-term use of the universally recognized IBM label, Lenovo has become the largest PC company in the world, thriving in an industry where rivals are struggling.

As part of its evolution, it has of course expanded beyond the ThinkPad brand in mobile computing. Lenovo offers IdeaPads to consumers and has introduced subbrands such as Miix and Helix as we have entered the era of laptops that twist and detach.

These designs have become one of the few growing PC segments. But back in the days when twisting and folding your screen would break your notebook, Lenovo jumpstarted the category with its first IdeaPad Yoga laptop. Designed to take advantage of the Microsoft push for laptops that could compete with tablets (specifically the then-red-hot iPad), the laptop's screen could rotate 360 degrees under its keyboard, essentially creating a thick tablet.

Lenovo deactivated the keyboard and trackpad when the Yoga was so positioned to eliminate errant input. It also released an accessory sleeve to cover the keys for those who disliked the idea of a tablet with an exposed keyboard on its backside. The laptop could also be posed in an inverted "V" or tent shape for presentations without the distraction of the keyboard.

Alas, the Windows RT operating system that the first Yoga used was an immense flop, beyond the aid of even the best hardware. But Lenovo persevered and quickly released a version based on standard Windows. A variation of its latest incarnation, the Yoga 900, comes in an exceptionally slim, gold-colored plastic body that offers the company's well-regarded manual keyboard and trackpad. It also offers an unusual USB-like power connector that connects to a plug so chunky that it somehow manages to prevent the use of outlets on either side of it, making a short extension cord a recommended accessory. Its most distinguishing visual feature, though, is Lenovo's visually polarizing "watch band" hinge, which provides very good stability at a range of angles.

But rather than leave Yoga as a brand representing a specific laptop form factor, Lenovo has evolved it in a different way than other company PC brands or, indeed, subbrands. First, it crossed over to tablets--unlikely device types, given their inherent simplicity. To provide the pose versatility embodied by the Yoga laptop, Lenovo added a metal flap that lies flush against the body attached to a cylindrical hinge. Adjusting this enables the Yoga to be propped up at a slight angle for typing or used as a kickstand for video.

As competitors have done, Lenovo has gone to higher-end configurations with its Yoga tablets, focusing more on the media consumption angle. With its latest incarnation, the Yoga Tablet 3 Pro, it has added a hole in the flap so you can hang the tablet on a wall like a picture frame. Lenovo has also improved the placement of a small projector that allows for an impromptu presentation or big-screen TV experience (provided a white, flat, vertical surface is available).

After crossing from Windows to Android, the Yoga brand has hopped back to the former with its extra-large touchscreen desktop PC, the Yoga Home 900. Keeping on point with its brand value, this "tabletop"--which can lay flat and run for a few hours on a battery--holds particular appeal for people engaged in collaborative computing. The Yoga brand took over this form factor from Lenovo's Horizon sub brand, and both were inspired by Microsoft's original Surface table computer, but at a fraction of the Surface's cost.

For consumers, a number of digital board games that run on the Yoga Home 900--such as Life, Risk, and Monopoly--are as engaging as their cardboard counterparts, and you never have to deal with missing pieces. This is also true for a number of supersized versions of smartphone and tablet games. However, while the Yoga desktop can be more productive than a similarly-sized Android device while in desktop mode, it has far fewer touch-friendly apps available for it. Even as that may improve in the Windows 10 era, it's still a long shot that many of them will be optimized for the lay-flat, multiuser scenario where the Yoga desktop excels.

The Yoga subbrand has uniquely embraced devices that cross and shift form factors. (Indeed, there is even a ThinkPad Yoga series.) Compared to the stoic corporate identity of many of Lenovo's devices, the Yoga line often looks avant-garde and incorporates innovations that are unique, at least among major brands. The future of its ability to serve as a testbed may depend upon whether shifting form factors can continue to capture customers' interest. Bridging such a transition may challenge even the Yoga brand's most outstretched pose.