The line between tablets and laptops is getting very blurry very fast. After all, except for high-end portable workstations and gaming rigs, a typical laptop PC is little more than a tablet with a keyboard. HP merges the two types beautifully with its Envy x2, creating a hybrid Windows 8 tablet/laptop that works equally well in both guises.

There are two ways to conceptualize the Envy x2. One way is to think of it as a notebook where the screen comes off and can be used as a tablet. It's better, though, to think of it as a tablet with an optional keyboard that also functions as a docking station. This docking station offers sundry connectors and a second battery.

If you're used to the traditional paradigm of a laptop PC, the keyboard base takes some getting used to. Of course, in a normal laptop, the guts are all located in the base of the computer and the screen is just that -- nothing more than a display. The Envy x2 turns this paradigm on its head. The screen includes the guts of the computer, including the CPU, memory, and storage. The keyboard includes nothing essential to running the computer, though it does include a second battery.

So, it's best to think of the keyboard base as more like a docking station than anything else. There are no moving parts of any kind inside the keyboard -- no DVD drive and no mechanical hard drive. Its main function, beyond providing a keyboard and touchpad, is to offer connectors for peripherals and for the power supply. The second battery provides the only real internal functionality.