The ThinkPad came long before the Apple iPad. Lenovo makes this clear in a video showing the genesis of the ThinkPad brand name, though the clip raises some pesky questions.
As some quick background--and as many readers probably know--a line of laptops using the same ThinkPad brand name ultimately became a hit for IBM, though the PC business overall didn't pan out financially for Big Blue, which sold it to Lenovo in 2004.
IBM was first: In the video, the Lenovo marketing executive (originally an IBM employee) talks about how IBM, in 1990, designed the ThinkPad 700T slate computer with a cutting-edge (at that time) magnesium case; how it used an "integrated heatsink" to obviate the need for a fan; and used a flash drive instead of a hard disk drive. Again, all of this way back in 1990.
While certainly an enlightening video, it still leaves one wondering why Lenovo is talking about this in the past tense. In other words, if IBM had such a head start in 1990, why is everyone fixated on Apple's tablet and why aren't we drooling over some highly evolved Lenovo Pad today? (Note: the Lenovo U1, though compelling, is a little late.)
I'm sure there are hundreds of reasons why IBM, and later Lenovo, didn't have a commercially successful consumer slate device (no, I'm not talking about a convertible laptop), but it seems odd that consumers have to wait for Apple to bring out a tablet before anyone takes serious notice of the slate computer.
So, what happened? Here's one facile answer. In the intervening 20 years, IBM sold off its PC business while Apple actually made a commercial success of innovative consumer designs and ballooned into one of the largest and most successful consumer device makers in the world.