Slide it, flip it or snap it on and off. The way keyboards are connected to touch screens on the latest generation of computing devices is making it tough to differentiate a tablet from notebook or an ultrabook.

Microsoft Corp, which has long been the dominant force in PCs but has fallen far behind in the tablet race, is set to unveil its Windows 8 operating system later this year, designed to run on super-thin laptops called ultrabooks and tablets powered by Intel Corp's chips.

The impending launch has prompted PC vendors to come up with a rash of hybrid designs, featuring touch screens and myriad configurations of moving or detachable keyboards.

"In future, it'll be a blur in the definition of an ultrabook and a tablet because of convertibles with either detachable or sliding keyboards," said Tracy Tsai, a Taipei-based analyst at research firm Gartner.

At Computex Taipei, the world's second largest computer show, visitors flocked to the booths trying out every twist and turn that converts an ultrabook into a tablet.

Lenovo Group Ltd's IdeaPad Yoga and Asustek Computer Inc's Taichi have screens that bend all the way back. Samsung Electronics' Hybrid becomes an ultrabook when the tablet clips onto a keyboard with magnetic hinges.

One tablet-ultrabook convertible that garnered attention was Asustek's Taichi, whose dual-sided screens can run different applications at the same time.

"There's a lot of use cases on tablets and tablet convertibles that people might approach with lots of fun, content consumption type of activity, but want to pop into it and use a productivity application and a desktop mode," said Chris Walker, Intel's director of microprocessor product marketing.

"The great thing is people don't have to make that choice."

BUT WILL THEY FLY?

Despite all the fanfare surrounding these hybrids from Microsoft, Intel and PC vendors banking on these gadgets to make up for lost time in the tablet sector, there remains some nervousness in the industry and uncertainty among consumers about whether they will take off in a big way.

"Most of us have a laptop for work and an Android or Apple tablet now, so whether I'll buy one of these hybrids will depend on the performance and price," said one Computex attendee in his 30s.

Prices for these touch-based ultrabook convertibles will not be announced until Windows 8 is formally released, widely expected to be in the fourth quarter.

But the hybrids are already prompting some analysts to ponder whether they should be classified as tablets or laptop PCs.

"A way to settle the argument is by the size of the gadget. Anything that is 10 inches or smaller should be categorized as a tablet, while those that are 11 inches or bigger should be called an ultrabook," said Ricky Liu, an analyst with KGI Securities.

Intel executives said they saw ultrabooks and its convertibles as laptops, while some PC vendors grouped such hybrids under tablets.

"Anything with a detachable keyboard is a tablet," said an Asustek executive as she clicked the Transformer screen back onto the keyboard at the company's booth at Computex.