Designers for Star Trek created flat, minimalist computers in order to save money. But as the franchise continued, the artists were forced to further explain the props' pretend functions, which eventually mirrored those of touch electronics today.
In a nifty interview with Ars Technica, the franchise's set designers explained how their pragmatism turned into prescience. Michael Okuda invented the show's omnipresent "Okudagrams," or the "interactive" colored panels that first appeared on Star Trek IV: The Voyage Home. Here, Okuda explains how cost restrictions forced designers to imagine the complex computing properties of the show's fake screens and devices.
The initial motivation for that was in fact cost [...] Doing it purely as a graphic was considerably less expensive than buying electronic components. But very quickly we began to realize-as we figured out how these things would work and how someone would operate them, people would come to me and say, 'What happens if I need to do this?' Perhaps it was some action I hadn't thought of, and we didn't have a specific control for that. And I realized the proper answer to that was, 'It's in the software.' All the things we needed could be software-definable. [...] We were considerably freer to imagine, 'What if you do this? Or what if you just touched that and it changed into a helm panel.'
For The Next Generation, the designers moved away from the electronic clipboards and created the multifunctional PADDs (Personal Access Display Devices), which Okuda notes could hypothetically pilot the Enterprise. Designer Doug Drexler explains how the PADDs tactile, nonspecific usage gave the devices an air of technosorcery. He also notes how the similarities between the PADDs and iPads is uncanny:
I think that anything that has no apparent mechanism yet delivers a big punch is either futuristic or, if you are from the Middle Ages, magic [...] Advanced alien devices on the original Trek series often had no discernible mechanism. So touch interfaces seem like magic. It's also slightly eerie, as you have the sensation that this thing is aware of you [...] We always felt that the classic Okuda T-bar graphic was malleable, and that you could stretch and rearrange it to suit your task, just like the iPad [...] The PADD never had a keyboard as part of its casing, just like the iPad. Its geometry is almost exactly the same-the corner radius, the thickness, and overall rectangular shape.
You can read the entire piece at Ars Technica here. Well, we're living with the devices of the final frontier today. Looks like it'll be your kids talking into the computer mouse.