Frustrated by another failed software installation? Wondering why you can't reproduce your colleagues' computations? This story will tell you why. It won't magically solve your problems, but it does point out a glimpse of hope for the future. It's one of those days in the life of a computational scientist. Your desktop computer is busy updating its operating system and doesn't have any time left for you. The installation of your favorite simulation software on the new supercomputer doesn't advance beyond an error message extending over 500 lines. And your data analysis hasn't made much progress either: the results change when you use more or fewer processors, which doesn't look right. You already asked Siri for advice, but as so often is the case, that conversation led absolutely nowhere. Computers are complex, frustrating machines. If only we could have simple ones that just did what we tell them to do! Maybe it's a good idea to go back to the basics. Ever heard of Turing machines? They were invented in 1937 by Alan Turing, 1 and they're as simple as computers can get. No keyboard, no screen, no hard disk-no operating system either, nor any voices pestering you. You write your instructions on a tape, put the tape into the machine, and push a button. The machine starts working, moving the tape back and forth. When it stops, you take out the tape again and read off the result. Computing couldn't be simpler! Turing invented the machine that was later named after him as a purely theoretical concept. There wasn't much real computing hardware available back then, but people eventually built physical realizations (www.legoturingmachine.org/lego-turing-machine, http://aturingmachine.com, and